Various improvements (#614)

- Auto-select widgets in Launcher and apps with toolbars on devices without touch.
- Improved USB HID input reliability, cleanup
- Updated PSRAM settings to improve boot stability on supported devices.
- Prevented duplicate Wi-Fi event subscriptions during screen rebuilds.
- Updated docs
- Fixes in WifiManage and WifiConnect
- Reduced main task stack size
- Moved USB HID stack size to PSRAM when available
- app_manager_find_manifest() now returns a copy instead of a pointer

.claude/rules/platform-abstraction.md

@@ -0,0 +1,4 @@
+# Architecture: Platform Abstraction
+
+- `Platforms/platform-esp32/` — ESP-IDF specific implementations
+- `Platforms/platform-posix/` — POSIX simulator implementations (SDL for display)