feat: Add auto-approval for mode switching

Implements automatic approval for mode switching operations when enabled, following
existing auto-approval patterns in the codebase.

Implementation:
- Added `alwaysAllowModeSwitch` to state management
- Updated `isAutoApproved` function in ChatView to handle mode switch requests
- Added mode switch option to AutoApproveMenu with appropriate handler
- Integrated with existing auto-approval flow

Tests:
- Added three test cases in ChatView.auto-approve.test.tsx:
  1. Verifies mode switch auto-approval when enabled
  2. Verifies no auto-approval when mode switch setting is disabled
  3. Verifies no auto-approval when global auto-approval is disabled

The implementation follows existing patterns for other auto-approve features
(read, write, browser, etc.) to maintain consistency in the codebase.

src/core/webview/ClineProvider.ts

@@ -79,6 +79,8 @@ type GlobalStateKey =
 	| "alwaysAllowWrite"
 	| "alwaysAllowExecute"
 	| "alwaysAllowBrowser"
+	| "alwaysAllowMcp"
+	| "alwaysAllowModeSwitch"
 	| "taskHistory"
 	| "openAiBaseUrl"
 	| "openAiModelId"
@@ -99,7 +101,6 @@ type GlobalStateKey =
 	| "soundEnabled"
 	| "soundVolume"
 	| "diffEnabled"
-	| "alwaysAllowMcp"
 	| "browserViewportSize"
 	| "screenshotQuality"
 	| "fuzzyMatchThreshold"
@@ -620,6 +621,10 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 						await this.updateGlobalState("alwaysAllowMcp", message.bool)
 						await this.postStateToWebview()
 						break
+					case "alwaysAllowModeSwitch":
+						await this.updateGlobalState("alwaysAllowModeSwitch", message.bool)
+						await this.postStateToWebview()
+						break
 					case "askResponse":
 						this.cline?.handleWebviewAskResponse(message.askResponse!, message.text, message.images)
 						break
@@ -1848,6 +1853,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 			alwaysAllowExecute,
 			alwaysAllowBrowser,
 			alwaysAllowMcp,
+			alwaysAllowModeSwitch,
 			soundEnabled,
 			diffEnabled,
 			taskHistory,
@@ -1882,6 +1888,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 			alwaysAllowExecute: alwaysAllowExecute ?? false,
 			alwaysAllowBrowser: alwaysAllowBrowser ?? false,
 			alwaysAllowMcp: alwaysAllowMcp ?? false,
+			alwaysAllowModeSwitch: alwaysAllowModeSwitch ?? false,
 			uriScheme: vscode.env.uriScheme,
 			clineMessages: this.cline?.clineMessages || [],
 			taskHistory: (taskHistory || [])
@@ -2009,6 +2016,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 			alwaysAllowExecute,
 			alwaysAllowBrowser,
 			alwaysAllowMcp,
+			alwaysAllowModeSwitch,
 			taskHistory,
 			allowedCommands,
 			soundEnabled,
@@ -2078,6 +2086,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 			this.getGlobalState("alwaysAllowExecute") as Promise<boolean | undefined>,
 			this.getGlobalState("alwaysAllowBrowser") as Promise<boolean | undefined>,
 			this.getGlobalState("alwaysAllowMcp") as Promise<boolean | undefined>,
+			this.getGlobalState("alwaysAllowModeSwitch") as Promise<boolean | undefined>,
 			this.getGlobalState("taskHistory") as Promise<HistoryItem[] | undefined>,
 			this.getGlobalState("allowedCommands") as Promise<string[] | undefined>,
 			this.getGlobalState("soundEnabled") as Promise<boolean | undefined>,
@@ -2166,6 +2175,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 			alwaysAllowExecute: alwaysAllowExecute ?? false,
 			alwaysAllowBrowser: alwaysAllowBrowser ?? false,
 			alwaysAllowMcp: alwaysAllowMcp ?? false,
+			alwaysAllowModeSwitch: alwaysAllowModeSwitch ?? false,
 			taskHistory,
 			allowedCommands,
 			soundEnabled: soundEnabled ?? false,