Hooks can render custom status (#385)

* Add ctx.ui.setStatus(key, text) API for hooks to display status in footer

- Add setStatus to HookUIContext interface
- Implement in interactive mode (FooterComponent)
- Implement in RPC mode (fire-and-forget)
- Add no-op implementations for headless contexts
- Multiple statuses displayed on single line, sorted by key
- Supports ANSI styling (hooks handle their own colors)

* Remove setStatus from changelog for now

* Fix hook status API to follow TUI rules

- Sanitize status text: replace newlines, tabs, carriage returns with spaces
- Truncate combined status line to terminal width using truncateToWidth
- Update JSDoc to document sanitization and truncation behavior
- Remove unused createHookUIContext method
- Add missing setStatus to test mock

* Add setStatus to changelog

* Use dim ellipsis for hook status truncation for consistency with footer style

---------

Co-authored-by: Mario Zechner <badlogicgames@gmail.com>

packages/coding-agent/src/core/custom-tools/loader.ts

@@ -90,6 +90,7 @@ function createNoOpUIContext(): HookUIContext {
 		confirm: async () => false,
 		input: async () => undefined,
 		notify: () => {},
+		setStatus: () => {},
 		custom: async () => undefined as never,
 		setEditorText: () => {},
 		getEditorText: () => "",

packages/coding-agent/src/core/hooks/runner.ts

@@ -39,6 +39,7 @@ const noOpUIContext: HookUIContext = {
 	confirm: async () => false,
 	input: async () => undefined,
 	notify: () => {},
+	setStatus: () => {},
 	custom: async () => undefined as never,
 	setEditorText: () => {},
 	getEditorText: () => "",

packages/coding-agent/src/core/hooks/types.ts

@@ -57,6 +57,17 @@ export interface HookUIContext {
 	 */
 	notify(message: string, type?: "info" | "warning" | "error"): void;
 
+	/**
+	 * Set status text in the footer/status bar.
+	 * Pass undefined as text to clear the status for this key.
+	 * Text can include ANSI escape codes for styling.
+	 * Note: Newlines, tabs, and carriage returns are replaced with spaces.
+	 * The combined status line is truncated to terminal width.
+	 * @param key - Unique key to identify this status (e.g., hook name)
+	 * @param text - Status text to display, or undefined to clear
+	 */
+	setStatus(key: string, text: string | undefined): void;
+
 	/**
 	 * Show a custom component with keyboard focus.
 	 * The factory receives TUI, theme, and a done() callback to close the component.