Update instructions to mention React + @legendapp/state

Author: celonymire

.github/copilot-instructions.md

@@ -3,14 +3,14 @@
 This repository contains a VS Code extension that provides two webview-based tools for competitive programming: **Judge** and **Stress**.
 
 - Extension backend code lives under `src/extension/**` and uses the VS Code API. `JudgeViewProvider` and `StressViewProvider` extend `BaseViewProvider`, which handles webview setup, CSP nonce generation, workspaceState storage, and message dispatch.
-- Webview frontend code lives under `src/webview/**` and is built with Preact + `@legendapp/state` for reactive state management. It talks to the extension only through typed messages defined in `src/shared/*-messages.ts`.
+- Webview frontend code lives under `src/webview/**` and is built with React + `@legendapp/state` for reactive state management. It talks to the extension only through typed messages defined in `src/shared/*-messages.ts`.
 - Shared enums, message contracts, and types live under `src/shared/**` and define the protocol between extension and webviews (including the `Status` lifecycle and testcase structures).
 
 Build and tooling:
 
 - Use `bun install` to install dependencies.
 - Use `bun run watch` during development and `bun run prod` for production builds. The build is two-stage: Tailwind CLI compiles `src/styles/global.css` to `dist/styles.css`, then Rspack bundles the extension and webviews into `dist/`.
-- Run `bun run lint` and `bun run format` to apply ESLint (TypeScript + Preact) and Prettier rules.
+- Run `bun run lint` and `bun run format` to apply ESLint (TypeScript + React) and Prettier rules.
 
 Design and implementation guidelines:
 

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

@@ -11,7 +11,7 @@ When working on the build, config, or tooling files matched by this pattern:
 - The build is two-stage:
   - `build:css`: Tailwind CLI reads from `src/styles/global.css` and writes `dist/styles.css`.
   - `build:js`: Rspack bundles the extension backend and webview frontends into `dist/`.
-- The Rspack configuration (`rspack.config.ts`) exports two configs: one targeting Node.js/CommonJS for the extension, and one targeting the web/ES modules for the webviews (TypeScript/TSX with Preact). Keep this separation intact when modifying the config.
+- The Rspack configuration (`rspack.config.ts`) exports two configs: one targeting Node.js/CommonJS for the extension, and one targeting the web/ES modules for the webviews (TypeScript/TSX with React). Keep this separation intact when modifying the config.
 - Type-checking is handled by ForkTsCheckerWebpackPlugin, using `tsconfig.node.json` for the extension and `tsconfig.app.json` for the webviews. Keep these project files aligned with the respective code trees.
-- For quality gates, use `bun run lint` (ESLint with TypeScript + Preact rules) and `bun run format` (Prettier). Avoid adding overlapping or conflicting linters/formatters.
+- For quality gates, use `bun run lint` (ESLint with TypeScript + React rules) and `bun run format` (Prettier). Avoid adding overlapping or conflicting linters/formatters.
 - Prefer minimal, focused config changes. Avoid introducing large new toolchains or build systems; extend the existing Rspack + Tailwind + Bun setup instead.

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

@@ -2,7 +2,7 @@
 applyTo: "src/webview/**/*.ts,src/webview/**/*.tsx"
 ---
 
-The `src/webview/**` tree contains the Preact-based frontend code for the Judge and Stress webviews. These run in an isolated browser-like environment, not in the VS Code extension host.
+The `src/webview/**` tree contains the React-based frontend code for the Judge and Stress webviews. These run in an isolated browser-like environment, not in the VS Code extension host.
 
 When changing files under `src/webview/**`: