build(android): install the debug build alongside release as its own app

Testing a debug build meant uninstalling the real one first: same
applicationId signed with a different key is INSTALL_FAILED_UPDATE_
INCOMPATIBLE, so every experiment cost the app's settings, credentials
and offline cache.

The debug build type now carries applicationIdSuffix ".debug" and
versionNameSuffix "-debug", so it installs as com.dtourolle.jellytau.debug
("JellyTau Debug", 0.5.5-debug) with its own data directory — two
independent apps on one device.

Only the *application* id is suffixed. Kotlin classes stay in the
`namespace` package com.dtourolle.jellytau, so the JNI loadClass lookups
in player/android/mod.rs, the manifest <service> entry and the R8 keep
rules are untouched, and the FileProvider authority was already
${applicationId}-relative. Launcher names come from the appLabel /
activityLabel manifestPlaceholders rather than resValue, which would
collide with Tauri's generated strings.xml; release resolves them back to
@string/app_name and merges byte-identical.

deploy-android.sh reports the target package and explains an
UPDATE_INCOMPATIBLE failure instead of leaving it raw; logcat.sh takes a
debug|release argument (it was filtering on com.jellytau.app, a package
that has never existed) and attaches by pid when the app is running.

Verified: aapt2 badging on the built APK reports
com.dtourolle.jellytau.debug / 0.5.5-debug / "JellyTau Debug", and the
release manifest merge is unchanged.

scripts/deploy-android.sh

@@ -16,10 +16,15 @@ fi
 # Build type: debug or release (default: debug)
 BUILD_TYPE="${1:-debug}"
 
+# The debug build carries applicationIdSuffix ".debug" (see
+# src-tauri/android/app/build.gradle.kts), so it is a separate package and
+# installs alongside a release build — no uninstall dance needed.
 if [ "$BUILD_TYPE" = "release" ]; then
     APK_PATH="src-tauri/gen/android/app/build/outputs/apk/universal/release/app-universal-release.apk"
+    APP_PACKAGE="com.dtourolle.jellytau"
 else
     APK_PATH="src-tauri/gen/android/app/build/outputs/apk/universal/debug/app-universal-debug.apk"
+    APP_PACKAGE="com.dtourolle.jellytau.debug"
 fi
 
 # Check if APK exists
@@ -30,8 +35,20 @@ if [ ! -f "$APK_PATH" ]; then
 fi
 
 echo "📦 Installing APK: $APK_PATH"
-adb install -r "$APK_PATH"
+echo "📛 Package: $APP_PACKAGE"
+
+if ! adb install -r "$APK_PATH"; then
+    echo ""
+    echo "❌ Install failed."
+    echo "   If it says INSTALL_FAILED_UPDATE_INCOMPATIBLE, an older build of"
+    echo "   '$APP_PACKAGE' signed with a different key is still installed."
+    echo "   Uninstall just that one and retry:"
+    echo "     adb uninstall $APP_PACKAGE"
+    exit 1
+fi
 
 echo ""
 echo "✅ Deployment complete!"
-echo "🚀 Launch the app on your device"
+echo "🚀 Launching..."
+adb shell monkey -p "$APP_PACKAGE" -c android.intent.category.LAUNCHER 1 > /dev/null 2>&1 \
+    || echo "   (auto-launch failed — start it from the launcher)"