feat(coding-agent): added self-update command with bundled templates

- Added `pi update` command for checking and installing CLI updates from GitHub releases or bun.
- Added cross-platform installer scripts (shell and PowerShell) with automatic PATH configuration.
- Changed HTML export to use compile-time bundled templates via Bun macros.
- Changed `exportToHtml` and `exportFromFile` functions to async operations.

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

@@ -2130,7 +2130,7 @@ export class InteractiveMode {
 
 		// HTML file export
 		try {
-			const filePath = this.session.exportToHtml(arg);
+			const filePath = await this.session.exportToHtml(arg);
 			this.showStatus(`Session exported to: ${filePath}`);
 		} catch (error: unknown) {
 			this.showError(`Failed to export session: ${error instanceof Error ? error.message : "Unknown error"}`);
@@ -2153,7 +2153,7 @@ export class InteractiveMode {
 		// Export to a temp file
 		const tmpFile = path.join(os.tmpdir(), "session.html");
 		try {
-			this.session.exportToHtml(tmpFile);
+			await this.session.exportToHtml(tmpFile);
 		} catch (error: unknown) {
 			this.showError(`Failed to export session: ${error instanceof Error ? error.message : "Unknown error"}`);
 			return;

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

@@ -401,7 +401,7 @@ export async function runRpcMode(session: AgentSession): Promise<never> {
 			}
 
 			case "export_html": {
-				const path = session.exportToHtml(command.outputPath);
+				const path = await session.exportToHtml(command.outputPath);
 				return success(id, "export_html", { path });
 			}