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/core/bash-executor.ts

@@ -13,6 +13,7 @@ import { join } from "node:path";
 import { type ChildProcess, spawn } from "child_process";
 import stripAnsi from "strip-ansi";
 import { getShellConfig, killProcessTree, sanitizeBinaryOutput } from "../utils/shell.js";
+import type { BashOperations } from "./tools/bash.js";
 import { DEFAULT_MAX_BYTES, truncateTail } from "./tools/truncate.js";
 
 // ============================================================================
@@ -177,3 +178,98 @@ export function executeBash(command: string, options?: BashExecutorOptions): Pro
 		});
 	});
 }
+
+/**
+ * Execute a bash command using custom BashOperations.
+ * Used for remote execution (SSH, containers, etc.).
+ */
+export async function executeBashWithOperations(
+	command: string,
+	cwd: string,
+	operations: BashOperations,
+	options?: BashExecutorOptions,
+): Promise<BashResult> {
+	const outputChunks: string[] = [];
+	let outputBytes = 0;
+	const maxOutputBytes = DEFAULT_MAX_BYTES * 2;
+
+	let tempFilePath: string | undefined;
+	let tempFileStream: WriteStream | undefined;
+	let totalBytes = 0;
+
+	const onData = (data: Buffer) => {
+		totalBytes += data.length;
+
+		// Sanitize: strip ANSI, replace binary garbage, normalize newlines
+		const text = sanitizeBinaryOutput(stripAnsi(data.toString("utf-8"))).replace(/\r/g, "");
+
+		// Start writing to temp file if exceeds threshold
+		if (totalBytes > DEFAULT_MAX_BYTES && !tempFilePath) {
+			const id = randomBytes(8).toString("hex");
+			tempFilePath = join(tmpdir(), `pi-bash-${id}.log`);
+			tempFileStream = createWriteStream(tempFilePath);
+			for (const chunk of outputChunks) {
+				tempFileStream.write(chunk);
+			}
+		}
+
+		if (tempFileStream) {
+			tempFileStream.write(text);
+		}
+
+		// Keep rolling buffer
+		outputChunks.push(text);
+		outputBytes += text.length;
+		while (outputBytes > maxOutputBytes && outputChunks.length > 1) {
+			const removed = outputChunks.shift()!;
+			outputBytes -= removed.length;
+		}
+
+		// Stream to callback
+		if (options?.onChunk) {
+			options.onChunk(text);
+		}
+	};
+
+	try {
+		const result = await operations.exec(command, cwd, {
+			onData,
+			signal: options?.signal,
+		});
+
+		if (tempFileStream) {
+			tempFileStream.end();
+		}
+
+		const fullOutput = outputChunks.join("");
+		const truncationResult = truncateTail(fullOutput);
+		const cancelled = options?.signal?.aborted ?? false;
+
+		return {
+			output: truncationResult.truncated ? truncationResult.content : fullOutput,
+			exitCode: cancelled ? undefined : (result.exitCode ?? undefined),
+			cancelled,
+			truncated: truncationResult.truncated,
+			fullOutputPath: tempFilePath,
+		};
+	} catch (err) {
+		if (tempFileStream) {
+			tempFileStream.end();
+		}
+
+		// Check if it was an abort
+		if (options?.signal?.aborted) {
+			const fullOutput = outputChunks.join("");
+			const truncationResult = truncateTail(fullOutput);
+			return {
+				output: truncationResult.truncated ? truncationResult.content : fullOutput,
+				exitCode: undefined,
+				cancelled: true,
+				truncated: truncationResult.truncated,
+				fullOutputPath: tempFilePath,
+			};
+		}
+
+		throw err;
+	}
+}