feat(lambda): Refactor and optimize Lambda Remote Invoke UI with enhanced payload management (#8068)

## Problem
Few UI feedback: 
- Payload is not intuitive
- Open Handler should be a button
Inconsistent layer behavior

## UI before
<img width="921" height="653" alt="image"
src="https://github.com/user-attachments/assets/0d7c2f27-78f6-453d-91fb-02ac00f2b043"
/>


## Solution
This PR refactors the Lambda Remote Invoke UI to follow VSCode's native
design patterns, optimizes the codebase by removing unused components,
and enhances the payload management experience with integrated quickpick
functionality for remote test events.

<img width="857" height="899" alt="image"
src="https://github.com/user-attachments/assets/1e446174-8cea-43a6-8ef1-44c1c8008c23"
/>

Update global layer version to 2

### 🎨 UI/UX Improvements

- __Redesigned Remote Debugging section__ to follow VSCode Settings UI
pattern

  - Title with inline "Remove Debug Setup" button and timer info
- Checkbox aligned with description on same line for better visual
hierarchy

- __Redesigned Local Root Path section__ with VSCode Settings style

  - Added "Open Handler" button with disabled state and helpful tooltips
- Shortened button labels to "Browse" and "Download" for cleaner
interface
  - Enhanced descriptions with bold text to guide user actions

- __Completely redesigned Payload section__

  - Removed radio buttons for cleaner, unified interface
- Added button group: "Load sample event", "Load local file", "Load
remote event", "Save as remote event"
  - Improved textarea with monospace font and better sizing

### 🚀 New Features

- __VSCode quickpick integration for remote test events__

- `selectRemoteTestEvent()`: Shows native quickpick for loading saved
events
- `saveRemoteTestEvent()`: Quickpick with options to create new or
overwrite existing events
  - Input validation for event names
  - Confirmation dialogs for overwriting existing events

- __Enhanced error handling__

- Gracefully handles "lambda-testevent-schemas registry not found" error
  - Returns empty array instead of throwing when no test events exist
  - Helpful user messages when no events are found

- __Force flag support__ for overwriting existing test events

  - Added `force` parameter to `SamCliRemoteTestEventsParameters`
  - Automatically uses `--force` when user confirms overwrite

###


---

- Treat all work as PUBLIC. Private `feature/x` branches will not be
squash-merged at release time.
- Your code changes must meet the guidelines in
[CONTRIBUTING.md](https://github.com/aws/aws-toolkit-vscode/blob/master/CONTRIBUTING.md#guidelines).
- License: I confirm that my contribution is made under the terms of the
Apache 2.0 license.

Author: roger-zhangg

packages/core/src/lambda/remoteDebugging/ldkClient.ts

@@ -302,6 +302,10 @@ export class LdkClient {
                 updatedEnv.ORIGINAL_AWS_LAMBDA_EXEC_WRAPPER = currentEnv['AWS_LAMBDA_EXEC_WRAPPER']
             }
 
+            if (getLogger().logLevelEnabled('debug')) {
+                updatedEnv.RUST_LOG = 'debug'
+            }
+
             // Create Lambda client using AWS SDK
             const lambda = this.getLambdaClient(region)
 

packages/core/src/lambda/remoteDebugging/ldkLayers.ts

@@ -31,7 +31,7 @@ export const regionToAccount: RegionAccountMapping = {
 }
 
 // Global layer version
-const globalLayerVersion = 1
+const globalLayerVersion = 2
 
 export function getRemoteDebugLayerForArch(region: string, arch: string): string | undefined {
     const account = regionToAccount[region]

packages/core/src/lambda/vue/remoteInvoke/invokeLambda.ts

@@ -102,19 +102,12 @@ export interface RuntimeDebugSettings {
 // UI state sub-interface
 export interface UIState {
     isCollapsed: boolean
-    showNameInput: boolean
-    payload: string
     extraRegionInfo: string
 }
 
 // Payload/Event handling sub-interface
 export interface PayloadData {
-    selectedSampleRequest: string
     sampleText: string
-    selectedFile: string
-    selectedFilePath: string
-    selectedTestEvent: string
-    newTestEventName: string
 }
 
 export interface RemoteInvokeData {
@@ -377,7 +370,7 @@ export class RemoteInvokeWebview extends VueWebview {
                 this.data.LambdaFunctionNode?.configuration.Handler
             )
             getLogger().warn(warning)
-            void vscode.window.showWarningMessage(warning)
+            void showMessage('warn', warning)
         }
         return fileLocations[0].fsPath
     }
@@ -443,22 +436,166 @@ export class RemoteInvokeWebview extends VueWebview {
     }
 
     public async listRemoteTestEvents(functionArn: string, region: string): Promise<string[]> {
-        const params: SamCliRemoteTestEventsParameters = {
-            functionArn: functionArn,
-            operation: TestEventsOperation.List,
-            region: region,
+        try {
+            const params: SamCliRemoteTestEventsParameters = {
+                functionArn: functionArn,
+                operation: TestEventsOperation.List,
+                region: region,
+            }
+            const result = await this.remoteTestEvents(params)
+            return result.split('\n').filter((event) => event.trim() !== '')
+        } catch (error) {
+            // Suppress "lambda-testevent-schemas registry not found" error - this is normal when no test events exist
+            const errorMessage = error instanceof Error ? error.message : String(error)
+            if (
+                errorMessage.includes('lambda-testevent-schemas registry not found') ||
+                errorMessage.includes('There are no saved events')
+            ) {
+                getLogger().debug('No remote test events found for function: %s', functionArn)
+                return []
+            }
+            // Re-throw other errors
+            throw error
+        }
+    }
+
+    public async selectRemoteTestEvent(functionArn: string, region: string): Promise<string | undefined> {
+        let events: string[] = []
+
+        try {
+            events = await this.listRemoteTestEvents(functionArn, region)
+        } catch (error) {
+            getLogger().error('Failed to list remote test events: %O', error)
+            void showMessage(
+                'error',
+                localize('AWS.lambda.remoteInvoke.failedToListEvents', 'Failed to list remote test events')
+            )
+            return undefined
+        }
+
+        if (events.length === 0) {
+            void showMessage(
+                'info',
+                localize(
+                    'AWS.lambda.remoteInvoke.noRemoteEvents',
+                    'No remote test events found. You can create one using "Save as remote event".'
+                )
+            )
+            return undefined
+        }
+
+        const selected = await vscode.window.showQuickPick(events, {
+            placeHolder: localize('AWS.lambda.remoteInvoke.selectRemoteEvent', 'Select a remote test event'),
+            title: localize('AWS.lambda.remoteInvoke.loadRemoteEvent', 'Load Remote Test Event'),
+        })
+
+        if (selected) {
+            const eventData = {
+                name: selected,
+                region: region,
+                arn: functionArn,
+            }
+            const resp = await this.getRemoteTestEvents(eventData)
+            return resp
         }
-        const result = await this.remoteTestEvents(params)
-        return result.split('\n')
+
+        return undefined
     }
 
-    public async createRemoteTestEvents(putEvent: Event) {
+    public async saveRemoteTestEvent(
+        functionArn: string,
+        region: string,
+        eventContent: string
+    ): Promise<string | undefined> {
+        let events: string[] = []
+
+        try {
+            events = await this.listRemoteTestEvents(functionArn, region)
+        } catch (error) {
+            // Log error but continue - user can still create new events
+            getLogger().debug('Failed to list existing remote test events (may not exist yet): %O', error)
+        }
+
+        // Create options for quickpick
+        const createNewOption = '$(add) Create new test event'
+        const options = events.length > 0 ? [createNewOption, ...events] : [createNewOption]
+
+        const selected = await vscode.window.showQuickPick(options, {
+            placeHolder: localize(
+                'AWS.lambda.remoteInvoke.saveEventChoice',
+                'Create new or overwrite existing test event'
+            ),
+            title: localize('AWS.lambda.remoteInvoke.saveRemoteEvent', 'Save as Remote Event'),
+        })
+
+        if (!selected) {
+            return undefined
+        }
+
+        let eventName: string | undefined
+
+        if (selected === createNewOption) {
+            // Prompt for new event name
+            eventName = await vscode.window.showInputBox({
+                prompt: localize('AWS.lambda.remoteInvoke.enterEventName', 'Enter a name for the test event'),
+                placeHolder: localize('AWS.lambda.remoteInvoke.eventNamePlaceholder', 'MyTestEvent'),
+                validateInput: (value) => {
+                    if (!value || value.trim() === '') {
+                        return localize('AWS.lambda.remoteInvoke.eventNameRequired', 'Event name is required')
+                    }
+                    if (events.includes(value)) {
+                        return localize(
+                            'AWS.lambda.remoteInvoke.eventNameExists',
+                            'An event with this name already exists'
+                        )
+                    }
+                    return undefined
+                },
+            })
+        } else {
+            // Use selected existing event name
+            const confirm = await showConfirmationMessage({
+                prompt: localize(
+                    'AWS.lambda.remoteInvoke.overwriteEvent',
+                    'Overwrite existing test event "{0}"?',
+                    selected
+                ),
+                confirm: localize('AWS.lambda.remoteInvoke.overwrite', 'Overwrite'),
+                cancel: 'Cancel',
+                type: 'warning',
+            })
+
+            if (confirm) {
+                eventName = selected
+            }
+        }
+
+        if (eventName) {
+            // Use force flag when overwriting existing events
+            const isOverwriting = selected !== createNewOption
+            const params: SamCliRemoteTestEventsParameters = {
+                functionArn: functionArn,
+                operation: TestEventsOperation.Put,
+                name: eventName,
+                eventSample: eventContent,
+                region: region,
+                force: isOverwriting,
+            }
+            await this.remoteTestEvents(params)
+            return eventName
+        }
+
+        return undefined
+    }
+
+    public async createRemoteTestEvents(putEvent: Event, force: boolean = false) {
         const params: SamCliRemoteTestEventsParameters = {
             functionArn: putEvent.arn,
             operation: TestEventsOperation.Put,
             name: putEvent.name,
             eventSample: putEvent.event,
             region: putEvent.region,
+            force: force,
         }
         return await this.remoteTestEvents(params)
     }
@@ -549,7 +686,8 @@ export class RemoteInvokeWebview extends VueWebview {
     // this serves as a lock for invoke
     public checkReadyToInvoke(): boolean {
         if (this.isInvoking) {
-            void vscode.window.showWarningMessage(
+            void showMessage(
+                'warn',
                 localize(
                     'AWS.lambda.remoteInvoke.invokeInProgress',
                     'A remote invoke is already in progress, please wait for previous invoke, or remove debug setup'
@@ -558,12 +696,14 @@ export class RemoteInvokeWebview extends VueWebview {
             return false
         }
         if (this.isStartingDebug) {
-            void vscode.window.showWarningMessage(
+            void showMessage(
+                'warn',
                 localize(
                     'AWS.lambda.remoteInvoke.debugSetupInProgress',
                     'A debugger setup is already in progress, please wait for previous setup to complete, or remove debug setup'
                 )
             )
+            return false
         }
         return true
     }