Update copilot instructions

Author: celonymire

.github/instructions/build-and-config.instructions.md

@@ -7,10 +7,32 @@ This repository uses npm, Rspack, TypeScript, and ESLint to build and lint the F
 When working on the build, config, or tooling files matched by this pattern:
 
 - Use `npm install` to install dependencies. Prefer npm scripts in `package.json` over ad-hoc commands.
+
+**Build System (Rspack):**
+
 - Builds are driven by **Rspack mode** (not `NODE_ENV`):
   - `npm run build` runs `rspack build --mode development`
   - `npm run watch` runs `rspack build --watch --mode development`
   - `npm run prod` runs `rspack build --mode production`
-- Use `npm run lint` to lint the codebase.
-- Use `npm run format` to apply Prettier formatting.
-- Use `npm run typecheck` to run Svelte type checking.
+- `rspack.config.ts` exports a dual configuration: one for the Node.js extension backend (`extensionConfig`) and one for the Svelte webviews (`webviewsConfig`).
+- Rspack uses `builtin:swc-loader` for fast transpilation and `ForkTsCheckerWebpackPlugin` for type checking.
+- Rspack automatically copies the compiled native addons (`.node` files) from `build/Release/` to `dist/` based on the host OS.
+
+**TypeScript Configuration:**
+
+- The project uses a composite TypeScript setup:
+  - `tsconfig.json`: Base configuration with project references.
+  - `tsconfig.node.json`: For the extension backend (`src/extension`) and shared code.
+  - `tsconfig.app.json`: For the webview frontend (`src/webview`) and shared code.
+
+**Linting & Formatting:**
+
+- Use `npm run lint` to lint the codebase. ESLint uses the Flat Config format (`eslint.config.mjs`) with `@typescript-eslint` (`projectService: true`) and supports Svelte 5 runes as globals.
+- Use `npm run format` to apply Prettier formatting, or `npm run check` to verify formatting.
+- Use `npm run svelte:check` to run Svelte type checking against `tsconfig.app.json`.
+
+**Native Addons & Packaging:**
+
+- Use `npm run build:addon` to compile the C++ process monitor addons via `node-gyp`.
+- Use `npm run test` to run the monitor tests.
+- Use `npm run package` to package the extension via `vsce`.

.github/instructions/extension-backend.instructions.md

@@ -19,24 +19,29 @@ Both Judge and Stress implement the same file-switching pattern:
 5. `_switchToNoFile()` handles cases where no valid file is open
 6. `_rehydrateWebviewFromState()` sends current in-memory state to the webview
 
-When switching files, stop any running processes for the previous file before switching to the new one.
+When switching files, processes are **not** stopped. Instead, they are moved to the background (e.g., via `_moveCurrentStateToBackground`) and trigger `_onDidChangeBackgroundTasks`. The `PanelViewProvider` monitors and displays these running background tasks.
 
-## TextHandler
+## Run Settings
 
-Use `TextHandler` from `src/extension/utils/vscode.ts` for all streamed output. It:
+- **`runSettingsCommands.ts`**: Registers commands (`editRunSettings`, `resetRunSettings`) and provides default `languageTemplates`.
+- **`vscode.ts`**: Provides `getFileRunSettings`, `initializeRunSettingsWatcher`, and `resolveVariables` to parse and resolve VS Code variables (like `${fileDirname}`) in commands.
 
-- Keeps full data internally for comparisons (answer checking)
-- Truncates display output (max characters/lines)
-- Normalizes CRLF to LF
-- Ensures trailing newline on final writes
+## Extended VS Code Utilities (`vscode.ts`)
 
-Write modes:
+- **`TextHandler`**: For all streamed output. Keeps full data internally, truncates display output, normalizes CRLF to LF, ensures trailing newline. Write modes: `"batch"`, `"force"`, `"final"`. Always call `.reset()` before a fresh run.
+- **`ReadonlyStringProvider`**: Manages the custom `fastolympiccoding` URI scheme for displaying read-only text documents.
+- **`openInNewEditor` / `openInTerminalTab`**: Helpers for displaying output. Terminal tabs support ANSI colors and native clickable file links.
+- **`openOrCreateFile`**: Helper for file management.
 
-- `"batch"`: Batched updates, throttled for performance
-- `"force"`: Immediate update, bypasses throttling
-- `"final"`: Final write, applies truncation rules and trailing newline
+## UI/UX Features
 
-Always call `.reset()` before a fresh run.
+- **Template Folding (`folding.ts`)**: `TemplateFoldingProvider` handles folding ranges for inserted template regions.
+- **Changelog (`changelog.ts`)**: `showChangelog` handles semver comparison and displays the changelog on extension updates.
+- **Status Bar (`statusBar.ts`)**: `createStatusBarItem` creates the main status bar entry point that triggers the `PanelViewProvider`.
+
+## Template Dependency Resolution
+
+`getTemplateContent` in `index.ts` handles reading template files and detecting cyclic dependencies via DFS before insertion.
 
 ## Runnable and runtime.ts
 
@@ -63,15 +68,15 @@ Debug support uses **attach mode**:
 3. Start debug-wrapped process via `Runnable`
 4. Call `vscode.debug.startDebugging()` with fully-resolved config
 
-Track debug sessions via `onDidStartDebugSession` / `onDidTerminateDebugSession`. Tag configs with `fastolympiccodingTestcaseId` to identify which testcase is being debugged.
+Track debug sessions via `onDidStartDebugSession` / `onDidTerminateDebugSession`. Tag configs with `fastolympiccodingTestcaseUuid` to identify which testcase is being debugged.
 
 ## Competitive Companion
 
 `competitiveCompanion.ts` implements an HTTP server receiving problem data from the browser extension. Problems are queued in `ProblemQueue` and processed sequentially. Users select target files via QuickPick for batch problems.
 
 ## Logging
 
-Use `getLogger(component)` from `src/extension/utils/logging.ts`. Component names: `"runtime"`, `"judge"`, `"stress"`, `"competitive-companion"`.
+Use `getLogger(component)` from `src/extension/utils/logging.ts`. Component names: `"runtime"`, `"judge"`, `"stress"`, `"competitive-companion"`, `"compilation"`, `"vscode"`.
 
 Log levels (controlled via VS Code's "Developer: Set Log Level"):
 

.github/instructions/judge-provider.instructions.md

@@ -53,7 +53,22 @@ Status determination uses `severityNumberToInteractiveStatus()` to combine both
 
 ## Action Handling
 
-The `handleMessage` method dispatches to action handlers based on `action` field:
+The `handleMessage` method dispatches based on `msg.type`. Top-level message types include:
+
+- `LOADED`: Loads the current file data
+- `NEXT`: Moves to the next testcase
+- `SAVE`: Saves testcase data
+- `VIEW`: Opens full stdio in a new editor
+- `COPY`: Copies stdio content to clipboard
+- `STDIN`: Updates stdin
+- `TL`: Updates time limit
+- `ML`: Updates memory limit
+- `REQUEST_TRIMMED_DATA`: Fetches truncated data for display
+- `REQUEST_FULL_DATA`: Fetches full data for editing
+- `NEW_INTERACTOR_SECRET`: Generates a new interactor secret
+- `ACTION`: Calls `this._action(msg)` which dispatches based on the `action` field
+
+Actions handled by `_action`:
 
 - `RUN`: Execute single testcase
 - `STOP`: Cancel running testcase
@@ -64,15 +79,17 @@ The `handleMessage` method dispatches to action handlers based on `action` field
 - `TOGGLE_SKIP`: Toggle skip flag
 - `COMPARE`: Open diff view
 - `DEBUG`: Run in debug mode
-- `REQUEST_DATA`: Fetch full data for editing
 - `OPEN_INTERACTOR`: Open interactor file
+- `TOGGLE_INTERACTIVE`: Toggle interactive mode
 
 ## Background Task Tracking
 
 `_contexts` map holds contexts for all files (not just active). Methods:
 
 - `getAllBackgroundTasks()`: Returns Map of file → running testcase UUIDs
+- `getBackgroundTasksForFile(file)`: Returns an array of running testcase UUIDs for a specific file
 - `stopBackgroundTasksForFile(file)`: Stop all running testcases for a file
+- `stopAllBackgroundTasks()`: Stops all background tasks across all files
 - `onDidChangeBackgroundTasks`: Event for PanelViewProvider to refresh
 
 ## Key Methods
@@ -82,3 +99,5 @@ The `handleMessage` method dispatches to action handlers based on `action` field
 - `_launchTestcase(ctx, bypassLimits, debugMode)`: Spawns process, wires stdio
 - `_launchInteractiveTestcase(ctx, bypassLimits, debugMode)`: Handles two-process interactive flow
 - `addTestcaseToFile(file, testcase, timeLimit?, memoryLimit?)`: Adds testcase from external source (Competitive Companion)
+- `exportTestcasesForFile(file)`: Serializes and exports testcases for a given file
+- `appendImportedTestcasesForFile(file, rawData)`: Parses, imports, and appends testcases to a file

.github/instructions/native-addon.instructions.md

@@ -17,7 +17,8 @@ Platform-specific native addons for strict process execution with:
 - Uses `pidfd_open` (kernel 5.3+) to avoid PID reuse races
 - Polls `/proc/[pid]/status` for `VmHWM` (Peak Resident Set Size)
 - **Critical**: Capture `VmHWM` before reaping zombie; values disappear after `wait4`
-- Memory enforcement via polling (50ms interval), not `RLIMIT_AS`
+- Memory enforcement via polling (10ms interval), not `RLIMIT_AS`
+- Uses `eventfd` to signal and wake the worker thread for cancellation
 
 ### macOS (`darwin-process-monitor.cpp`)
 
@@ -29,15 +30,17 @@ Platform-specific native addons for strict process execution with:
 
 - Uses **Job Objects** for hard memory/CPU limits (OS-enforced)
 - Process created suspended, added to Job, then resumed
-- Uses completion ports for efficient wait
+- Uses `WaitForMultipleObjects` with a polling loop to handle process exit, cancellation events, and wall-clock timeouts
 - **All APIs use Wide Strings** (`CreateProcessW`, `std::wstring`)
 
 ## Spawn API
 
 ```typescript
+// Spawn function signature
+// spawn(command, args, cwd, timeoutMs, memoryLimitMB, pipeNameIn, pipeNameOut, pipeNameErr, onSpawn)
+
 interface NativeSpawnResult {
   pid: number;
-  stdio: [number, number, number]; // fd handles
   result: Promise<AddonResult>;
   cancel: () => void;
 }
@@ -54,7 +57,7 @@ interface AddonResult {
 
 ## IPC
 
-Stdio uses Named Pipes (Windows) or Unix Sockets (Linux/macOS) established before process spawn. The extension's `Runnable` class connects to these pipes.
+Stdio uses Named Pipes (Windows) or Unix Sockets (Linux/macOS). The extension creates the pipes/sockets and passes their paths to the addon's `spawn` function, which then connects to them internally before executing the child process.
 
 ## Cancellation
 

.github/instructions/shared-contracts.instructions.md

@@ -8,7 +8,7 @@ applyTo: "src/shared/**/*.ts"
 
 ## Enums (String Literal Tuples)
 
-Enums are `const` string literal tuples validated via `v.picklist()`:
+Enums are `const` string literal tuples validated via `v.picklist()`. All string literal tuples (including `ActionValues`, `InputTypeValues`, `ProviderMessageTypeValues`, `WebviewMessageTypeValues`, etc.) follow the same append-only rule.
 
 ### Status
 
@@ -74,9 +74,19 @@ StateIdValue = ["Generator", "Solution", "Judge"] as const;
 
 ## Schema Patterns
 
-Use Valibot for all schemas. Pattern:
+Use Valibot for all schemas.
+
+### Message Type Arrays
+
+When adding a new message schema, its `type` literal **must** also be appended to the corresponding `ProviderMessageTypeValues` or `WebviewMessageTypeValues` array. This prevents the arrays from falling out of sync with the union schemas.
 
 ```typescript
+export const ProviderMessageTypeValues = [
+  "EXAMPLE",
+  "OTHER",
+  // Append new types here
+] as const;
+
 export const ExampleMessageSchema = v.object({
   type: v.literal("EXAMPLE"),
   payload: v.string(),
@@ -90,6 +100,20 @@ export const AllMessagesSchema = v.union([ExampleMessageSchema, OtherMessageSche
 export type AllMessages = v.InferOutput<typeof AllMessagesSchema>;
 ```
 
+### Advanced Valibot Patterns
+
+- **Default Values:** Use `v.fallback()` to provide default state values (e.g., `v.fallback(v.string(), "")` or `v.fallback(v.string(), () => crypto.randomUUID())`).
+- **Complex Validation:** Use `v.pipe()`, `v.looseObject()`, and `v.check()` for custom validation logic (e.g., in `RunSettingsSchema`).
+- **Optional & Record Types:** Use `v.optional()` and `v.record()` for flexible configurations.
+
+### Type Inference and Utility Types
+
+Derive property types from schemas using TypeScript utility types. For example:
+
+```typescript
+export type TestcaseProperty = Exclude<keyof Testcase, "uuid">;
+```
+
 ## Append-Only Rule
 
 When adding new enum values or message types, **append to the end** of arrays. Never rename or reorder existing values—they may be persisted in workspaceState.

.github/instructions/stress-provider.instructions.md

@@ -69,34 +69,38 @@ interface State {
 In interactive mode:
 
 - Generator produces a "secret" (like interactor in Judge)
-- Solution and Judge run with Generator mediating
+- The **Judge** acts as the interactor (running `interactorFile`), communicating back and forth with the **Solution** (the user's solution).
+- The **Generator** provides the initial secret to the Judge.
 - Uses `interactiveSecretPromise` to wait for webview to receive the secret
-- Solution runs as interactor between Generator and user solution
 
 ## State Persistence
 
-Persisted per-file data:
+Persisted per-file data via `StressDataSchema` in `_saveState`:
 
 - `interactiveMode`: boolean
-- `states`: Array of `{ state: StateId, shown: boolean }`
+- `states`: Array of `{ state: StateId, shown: boolean, stdin: string, stdout: string, stderr: string, status: Status }`
 
-The stdio content is NOT persisted (only visibility state).
+The stdio content, status, state, and visibility are all persisted for each component.
 
 ## Message Handling
 
+- `LOADED`: Loads the current file data
 - `RUN`: Start stress loop
 - `STOP`: Set stopFlag, stop current iteration
 - `VIEW`: Open full stdio in new editor
+- `COPY`: Copies specific stdio content to the clipboard
 - `ADD`: Copy Generator output to Judge testcases
 - `OPEN`: Open the corresponding file (generator/judge file)
 - `CLEAR`: Stop and clear all state
 - `SAVE`: Persist interactiveMode setting
 - `TOGGLE_VISIBILITY`: Toggle state details visibility
+- `TOGGLE_INTERACTIVE`: Toggles the interactive mode state
 
 ## Background Task Tracking
 
 - `getRunningStressSessions()`: Returns array of file paths with running stress
 - `stopStressSession(file)`: Stop stress for a specific file
+- `stopAll()`: Stops all stress sessions across all files in the workspace
 - `onDidChangeBackgroundTasks`: Event for PanelViewProvider
 
 ## Key Methods

.github/instructions/webview-frontend.instructions.md

@@ -25,27 +25,37 @@ Receive messages in `App.svelte` via `window.addEventListener("message", ...)` i
 
 - **App.svelte**: Entry point, message handling, testcase list rendering
 - **TestcaseToolbar.svelte**: Status badges, action buttons (run, stop, debug, delete)
-- **Testcase.svelte**: Stdio textareas (stdin, stdout, stderr, acceptedStdout)
+- **Testcase.svelte**: Stdio textareas (stdin, stdout, stderr, acceptedStdout, interactorSecret)
 
 Rendering pattern:
 
 ```svelte
-{#each testcases as testcase (testcase.uuid)}
-  <TestcaseToolbar {testcase} onprerun={() => handlePrerun(testcase.uuid)} />
-  <Testcase {testcase} bind:this={testcaseRefs[testcase.uuid]} />
+{#each testcases as testcase, index (testcase.uuid)}
+  <div class="testcase-item">
+    <TestcaseToolbar {testcase} onprerun={() => handlePrerun(testcase.uuid)} />
+    {#if testcase.status === "COMPILING" || testcase.skipped}
+      <div class="half-opacity">
+        <Testcase bind:testcase={testcases[index]} bind:this={testcaseRefs[testcase.uuid]} />
+      </div>
+    {:else}
+      <Testcase bind:testcase={testcases[index]} bind:this={testcaseRefs[testcase.uuid]} />
+    {/if}
+  </div>
 {/each}
 ```
 
 ### Stress View (`src/webview/stress/`)
 
 - **App.svelte**: Entry point, message handling, state list rendering
-- **StateToolbar.svelte**: Status badges, action buttons (add, open file)
+- **StateToolbar.svelte**: Status badges, action buttons (add, open file, toggle interactive mode)
 - **State.svelte**: Stdio textareas for Generator/Solution/Judge
 
 ### Shared Components (`src/webview/`)
 
 - **AutoresizeTextarea.svelte**: Resizable textarea with ANSI color support
 - **Tooltip.svelte**: Global tooltip singleton
+- **Button.svelte**: Standard button component
+- **ButtonDropdown.svelte**: Composite component providing a main button alongside a dropdown menu
 
 ## AutoresizeTextarea
 
@@ -56,14 +66,20 @@ Key props:
 - `editing`: Bindable, tracks edit mode
 - `hiddenOnEmpty`: Hide when empty
 - `variant`: `"default"` | `"stderr"` | `"accepted"` | `"active"` | `"interactor-secret"`
+- `placeholder`: Text to display when empty
+- `ctrlEnterNewline`: Boolean to toggle specific Ctrl+Enter newline behavior
+- `actions`: A Svelte `Snippet` prop for injecting custom action buttons into the textarea overlay
 
-Editing callbacks:
+Callbacks:
 
 - `onpreedit`: Called before entering edit mode (fetch full data from extension)
 - `onsave`: Called when saving changes
 - `oncancel`: Called when canceling edit
+- `onexpand`: Called when the user clicks the expand icon (to view full stdio)
+- `oncopy`: Called when the user clicks the copy icon
+- `onkeyup`: Keyboard event handler
 
-Pattern for fetching full data on edit:
+Pattern for fetching full data on edit and handling actions:
 
 ```svelte
 <AutoresizeTextarea
@@ -76,6 +92,8 @@ Pattern for fetching full data on edit:
   oncancel={() => {
     postProviderMessage({ type: "REQUEST_TRIMMED_DATA", uuid: testcase.uuid, stdio: "STDIN" });
   }}
+  onexpand={() => handleExpand("STDIN")}
+  oncopy={() => handleCopy("STDIN")}
 />
 ```