Add app source and tests

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

lib/main.dart

@@ -0,0 +1,33 @@
+import 'package:flutter/material.dart';
+
+import 'Peach/configs/ThemeController.dart';
+import 'Peach/designs/Backdrop.dart';
+import 'Peach/see/splash/Splash.dart';
+import 'Peach/utils/Colors.dart';
+
+void main() {
+  runApp(const Peach());
+}
+
+/// The app shell: theme, the glow backdrop, and the splash that loads stored
+/// state before handing over to Home. Everything else lives under
+/// `lib/Peach/see/` as a four-file screen.
+class Peach extends StatelessWidget {
+  const Peach({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return ValueListenableBuilder<ThemeMode>(
+      valueListenable: ThemeController.mode,
+      builder: (context, mode, child) => MaterialApp(
+        title: 'Peach',
+        debugShowCheckedModeBanner: false,
+        theme: PeachTheme.light(),
+        darkTheme: PeachTheme.dark(),
+        themeMode: mode,
+        builder: (context, child) => Backdrop(child: child ?? const SizedBox()),
+        home: const Splash(),
+      ),
+    );
+  }
+}