Sublime-style Build-n versioning + About box

Build n = commit count, baked at build time into a gitignored
version.gen.ts (postinstall + all build scripts regenerate it). About
lives in the macOS app menu and as a footer row in the options popover
(the cross-platform path), showing build, commit, date and engines.

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

src/bun/index.ts

@@ -51,6 +51,7 @@ const events = {
 	openEditor: (_ctx: EditorOpenContext) => {},
 	settingsChanged: (_settings: AppSettings) => {},
 	openConnectionManager: () => {},
+	showAbout: () => {},
 };
 const rpc = createAppRPC({ registry, engine, store, settings, edits, contextMenu, events });
 const url = await getMainViewUrl();
@@ -104,6 +105,20 @@ events.settingsChanged = (s) => {
 	manager.broadcastSettings(s);
 };
 events.openConnectionManager = () => manager.open();
+
+function showAbout(): void {
+	const { build } = BRANDING;
+	void Utils.showMessageBox({
+		type: "info",
+		title: BRANDING.appName,
+		message: BRANDING.appName,
+		detail: `${BRANDING.buildLabel} (${build.commit}) · ${build.date}\n\nElectrobun ${build.electrobun} · Bun ${Bun.version}`,
+		buttons: ["OK"],
+		defaultId: 0,
+		cancelId: 0,
+	});
+}
+events.showAbout = showAbout;
 // clean editors close with the main window; dirty ones get to ask first,
 // and the modal manager has nothing to guard
 win.on("close", () => {
@@ -204,6 +219,10 @@ ApplicationMenu.on("application-menu-clicked", (event) => {
 		manager.open();
 		return;
 	}
+	if (action === "about") {
+		showAbout();
+		return;
+	}
 	// the manager is modal to the main window — don't drive main behind it
 	if (manager.isOpen()) return;
 	rpc.send.menuAction({ action });

src/bun/menu.ts

@@ -1,4 +1,5 @@
 import { ApplicationMenu, type ApplicationMenuItemConfig } from "electrobun/bun";
+import { BRANDING } from "../shared/branding";
 import type { SavedConnection } from "../shared/types";
 import type { ConnectionStore } from "./store/connections";
 
@@ -32,6 +33,8 @@ export async function applyApplicationMenu(store: ConnectionStore): Promise<void
 	ApplicationMenu.setApplicationMenu([
 		{
 			submenu: [
+				{ label: `About ${BRANDING.appName}`, action: "about" },
+				{ type: "separator" },
 				{ role: "hide" },
 				{ role: "hideOthers" },
 				{ role: "showAll" },

src/bun/rpc-handlers.ts

@@ -30,6 +30,7 @@ export interface AppDeps {
 		openEditor: (ctx: EditorOpenContext) => void;
 		settingsChanged: (settings: AppSettings) => void;
 		openConnectionManager: () => void;
+		showAbout: () => void;
 	};
 }
 
@@ -294,6 +295,12 @@ export function createAppRPC({
 						events.openConnectionManager();
 						return {};
 					}),
+
+				showAbout: () =>
+					wrap(async () => {
+						events.showAbout();
+						return {};
+					}),
 			},
 		},
 	});