Editor opens in native windows (one per file)

Real BrowserWindow per edited file with its own RPC instance, deduped by
sessionId+path. The same Angular bundle boots an editor-only root via
preload globals. Native close isn't cancellable in electrobun, so the
editor mirrors its draft to bun; traffic-light closes get a native
Save/Discard prompt after the fact, and failed saves park the draft in
the edit-leftovers dir. In-window closes (Cmd+W, Close) use a styled
prompt; the quit guard now also counts unsaved editors.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/bun/edits.ts

@@ -134,6 +134,21 @@ export class EditManager {
 		});
 	}
 
+	/**
+	 * Park unsaveable editor content (window closed, session dead) in the
+	 * leftovers dir so the next-boot prompt offers it back to the user.
+	 */
+	async rescueDraft(name: string, content: string): Promise<void> {
+		const dir = path.join(this.editsDir, crypto.randomUUID().slice(0, 8));
+		await fs.mkdir(dir, { recursive: true });
+		await fs.writeFile(
+			path.join(dir, "meta.json"),
+			JSON.stringify({ name, rescuedAt: new Date().toISOString() }),
+		);
+		await fs.writeFile(path.join(dir, name), content, "utf8");
+		console.log(`[edit] rescued unsaved draft of ${name} -> ${dir}`);
+	}
+
 	/** Session gone (disconnect, tab close, death): stop its watchers, drop temps. */
 	stopForSession(sessionId: string): void {
 		const [mine, rest] = [