feat(coding-agent): added configurable ask timeout/notifications and centralized process execution

- Added configurable ask timeout and notification settings to control ask tool behavior and user notifications.
- Added AskSettings interface with timeout (in seconds, default 30) and notification method properties to settings manager.
- Added ask timeout and notification configuration options to settings UI with values for timeout (off, 15, 30, 60, 120 seconds) and notification methods (auto, bell, osc99, osc9, off).
- Refactored process execution across multiple tools (exec, fetch, grep, read, youtube scraper) to use centralized ptree.execText() API instead of custom implementations.
- Refactored ChildProcess class in ptree to use public readonly properties and Promise.withResolvers() for cleaner exit handling.

packages/coding-agent/src/exec/bash-executor.ts

@@ -65,9 +65,8 @@ export async function executeBash(command: string, options?: BashExecutorOptions
 
 	// Wait for process exit
 	try {
-		await child.exited;
 		return {
-			exitCode: child.exitCode ?? 0,
+			exitCode: await child.exited,
 			cancelled: false,
 			...(await sink.dump()),
 		};