perf(android): R8, bitmap downscaling, edge-to-edge; recover device compat; publish to production

Device compatibility (regression fix):
- The CAMERA permission (from zxing_barcode_scanner / image_picker) implicitly
  required android.hardware.camera, excluding camera-less devices — Play showed
  Automotive -96%, Chromebook -86%, TV -25%. Declare camera & location
  uses-feature required="false" to keep those devices supported.
- Detect a real camera at runtime (PackageManager.FEATURE_CAMERA_ANY via the
  existing MethodChannel), cache it at bootstrap, and hide the QR scan button and
  the camera photo-source option when absent, so no broken actions are offered.

Play "app optimization" recommendations:
- Enable R8 (isMinifyEnabled + isShrinkResources) with keep rules for the
  OCR (tesseract4android), SQLCipher and notifications JNI/reflection code.
- Bitmap downscaling: cacheWidth/cacheHeight (and ResizeImage for avatars) on
  list thumbnails and avatars so photos decode to on-screen size, not full res.
- Edge-to-edge: opt in with transparent system bars in main().

Release flow:
- Tagged builds now publish to the production track at 100% (was internal);
  add a manual deploy_internal lane as a QA safety net.
- Document country/region availability as a Play Console setting (not in-repo).

apps/app_seeds/fastlane/Fastfile

@@ -16,13 +16,24 @@ default_platform(:android)
 AAB_PATH = "build/app/outputs/bundle/release/app-release.aab".freeze
 
 platform :android do
-  desc "Upload the signed AAB + store listing to Google Play (internal track)"
+  desc "Upload the signed AAB + store listing to Google Play (production, 100%)"
   lane :deploy_play do
+    supply(
+      track: "production",
+      aab: AAB_PATH,
+      release_status: "completed", # publish to 100% of users (subject to review)
+      skip_upload_apk: true,       # we ship the AAB, not a raw APK
+      skip_upload_changelogs: false,
+    )
+  end
+
+  desc "Upload the signed AAB to the internal test track (manual QA safety net)"
+  lane :deploy_internal do
     supply(
       track: "internal",
       aab: AAB_PATH,
       release_status: "completed", # internal testing has no review delay
-      skip_upload_apk: true,       # we ship the AAB, not a raw APK
+      skip_upload_apk: true,
       skip_upload_changelogs: false,
     )
   end