Add radial mode, UI controls, front camera, update to API 35

- Add radial/elliptical blur mode with aspect ratio control
- Add UI sliders for blur intensity, falloff, and shape
- Add front camera support with flip button
- Update minimum SDK to API 35 (Android 15)
- Enable landscape orientation (fullSensor)
- Rename app to "Naiv Tilt Shift Camera"
- Set APK output name to naiv-tilt-shift
- Add project specification document

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/src/main/AndroidManifest.xml

@@ -28,7 +28,8 @@
         <activity
             android:name=".MainActivity"
             android:exported="true"
-            android:screenOrientation="portrait"
+            android:screenOrientation="fullSensor"
+            android:configChanges="orientation|screenSize|screenLayout|keyboardHidden"
             android:windowSoftInputMode="adjustResize"
             android:theme="@style/Theme.TiltShiftCamera">
             <intent-filter>