Build and run the app on Android

The editor's fork moves to keyboard_height_plugin v0.3.0 (83bdb2a3): v0.1.5
compiled against API 31, while the AndroidX libraries of Flutter v3.47 need
34, so Gradle's AAR metadata check failed. Release builds get the internet
permission, which Flutter's template grants to debug and profile builds
only. Gradle's own build folder in android/ (its problems report) is
ignored. AGENTS.md: the server's test/integration/test_tools/ is generated
too, so test files are formatted one by one.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

halkyon_learn_flutter/android/.gitignore

@@ -1,6 +1,8 @@
 gradle-wrapper.jar
 /.gradle
 /captures/
+# Gradle's own build output, e.g. its problems report.
+/build/
 /gradlew
 /gradlew.bat
 /local.properties

halkyon_learn_flutter/android/app/src/main/AndroidManifest.xml

@@ -1,4 +1,7 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- The app syncs with its server: release builds need this too (Flutter's
+         template grants it to debug and profile builds only). -->
+    <uses-permission android:name="android.permission.INTERNET"/>
     <application
         android:label="Halkyon Learn"
         android:name="${applicationName}"

halkyon_learn_flutter/pubspec.yaml

@@ -29,7 +29,7 @@ dependencies:
   appflowy_editor:
     git:
       url: https://code.halkyon.app/project-halkyon/appflowy-editor.git
-      ref: 0dac8a046e91ac89c0ffa13e2d603ebf50873332
+      ref: 83bdb2a3e66881eff9b2f8afe416b57fc791daf9
   # Anki packages are zip files.
   archive: ^4.0.7
   # Sounds in content (pronunciations): one package for all five platforms; on