feat(coding-agent): add user_bash event and theme API extensions

- user_bash event for intercepting ! and !! commands (#528)
- Extensions can return { operations } or { result } to redirect/replace
- executeBashWithOperations() for custom BashOperations execution
- session.recordBashResult() for extensions handling bash themselves
- Theme API: getAllThemes(), getTheme(), setTheme() on ctx.ui
- mac-system-theme.ts example: sync with macOS dark/light mode
- Updated ssh.ts to use user_bash event

packages/coding-agent/src/modes/interactive/interactive-mode.ts

@@ -75,12 +75,15 @@ import { UserMessageComponent } from "./components/user-message.js";
 import { UserMessageSelectorComponent } from "./components/user-message-selector.js";
 import {
 	getAvailableThemes,
+	getAvailableThemesWithPaths,
 	getEditorTheme,
 	getMarkdownTheme,
+	getThemeByName,
 	initTheme,
 	onThemeChange,
 	setTheme,
-	type Theme,
+	setThemeInstance,
+	Theme,
 	theme,
 } from "./theme/theme.js";
 
@@ -937,6 +940,20 @@ export class InteractiveMode {
 			get theme() {
 				return theme;
 			},
+			getAllThemes: () => getAvailableThemesWithPaths(),
+			getTheme: (name) => getThemeByName(name),
+			setTheme: (themeOrName) => {
+				if (themeOrName instanceof Theme) {
+					setThemeInstance(themeOrName);
+					this.ui.requestRender();
+					return { success: true };
+				}
+				const result = setTheme(themeOrName, true);
+				if (result.success) {
+					this.ui.requestRender();
+				}
+				return result;
+			},
 		};
 	}
 
@@ -3140,6 +3157,50 @@ export class InteractiveMode {
 	}
 
 	private async handleBashCommand(command: string, excludeFromContext = false): Promise<void> {
+		const extensionRunner = this.session.extensionRunner;
+
+		// Emit user_bash event to let extensions intercept
+		const eventResult = extensionRunner
+			? await extensionRunner.emitUserBash({
+					type: "user_bash",
+					command,
+					excludeFromContext,
+					cwd: process.cwd(),
+				})
+			: undefined;
+
+		// If extension returned a full result, use it directly
+		if (eventResult?.result) {
+			const result = eventResult.result;
+
+			// Create UI component for display
+			this.bashComponent = new BashExecutionComponent(command, this.ui, excludeFromContext);
+			if (this.session.isStreaming) {
+				this.pendingMessagesContainer.addChild(this.bashComponent);
+				this.pendingBashComponents.push(this.bashComponent);
+			} else {
+				this.chatContainer.addChild(this.bashComponent);
+			}
+
+			// Show output and complete
+			if (result.output) {
+				this.bashComponent.appendOutput(result.output);
+			}
+			this.bashComponent.setComplete(
+				result.exitCode,
+				result.cancelled,
+				result.truncated ? ({ truncated: true, content: result.output } as TruncationResult) : undefined,
+				result.fullOutputPath,
+			);
+
+			// Record the result in session
+			this.session.recordBashResult(command, result, { excludeFromContext });
+			this.bashComponent = undefined;
+			this.ui.requestRender();
+			return;
+		}
+
+		// Normal execution path (possibly with custom operations)
 		const isDeferred = this.session.isStreaming;
 		this.bashComponent = new BashExecutionComponent(command, this.ui, excludeFromContext);
 
@@ -3162,7 +3223,7 @@ export class InteractiveMode {
 						this.ui.requestRender();
 					}
 				},
-				{ excludeFromContext },
+				{ excludeFromContext, operations: eventResult?.operations },
 			);
 
 			if (this.bashComponent) {

packages/coding-agent/src/modes/interactive/theme/theme.ts

@@ -456,6 +456,36 @@ export function getAvailableThemes(): string[] {
 	return Array.from(themes).sort();
 }
 
+export interface ThemeInfo {
+	name: string;
+	path: string | undefined;
+}
+
+export function getAvailableThemesWithPaths(): ThemeInfo[] {
+	const themesDir = getThemesDir();
+	const customThemesDir = getCustomThemesDir();
+	const result: ThemeInfo[] = [];
+
+	// Built-in themes
+	for (const name of Object.keys(getBuiltinThemes())) {
+		result.push({ name, path: path.join(themesDir, `${name}.json`) });
+	}
+
+	// Custom themes
+	if (fs.existsSync(customThemesDir)) {
+		for (const file of fs.readdirSync(customThemesDir)) {
+			if (file.endsWith(".json")) {
+				const name = file.slice(0, -5);
+				if (!result.some((t) => t.name === name)) {
+					result.push({ name, path: path.join(customThemesDir, file) });
+				}
+			}
+		}
+	}
+
+	return result.sort((a, b) => a.name.localeCompare(b.name));
+}
+
 function loadThemeJson(name: string): ThemeJson {
 	const builtinThemes = getBuiltinThemes();
 	if (name in builtinThemes) {
@@ -532,6 +562,14 @@ function loadTheme(name: string, mode?: ColorMode): Theme {
 	return createTheme(themeJson, mode);
 }
 
+export function getThemeByName(name: string): Theme | undefined {
+	try {
+		return loadTheme(name);
+	} catch {
+		return undefined;
+	}
+}
+
 function detectTerminalBackground(): "dark" | "light" {
 	const colorfgbg = process.env.COLORFGBG || "";
 	if (colorfgbg) {
@@ -596,6 +634,12 @@ export function setTheme(name: string, enableWatcher: boolean = false): { succes
 	}
 }
 
+export function setThemeInstance(themeInstance: Theme): void {
+	theme = themeInstance;
+	currentThemeName = "<in-memory>";
+	stopThemeWatcher(); // Can't watch a direct instance
+}
+
 export function onThemeChange(callback: () => void): void {
 	onThemeChangeCallback = callback;
 }