Fix Gradle and Rust cache save failures on parallel release jobs.

Use scope-specific Gradle cache paths, global release concurrency, Rust v3 key with v1/v2 fallbacks, and ensure Android SDK cache dirs exist before save.

Co-authored-by: Cursor <cursoragent@cursor.com>

.github/actions/cache-gradle-build/action.yml

@@ -9,7 +9,7 @@ inputs:
 outputs:
   cache-hit:
     description: Whether an exact cache key match was restored
-    value: ${{ steps.cache.outputs.cache-hit }}
+    value: ${{ steps.cache.outputs.cache-hit == 'true' || steps.cache-android.outputs.cache-hit == 'true' }}
   cache-save-scope:
     description: Scope to pass to the save action (always this job's scope, not a restored fallback key)
     value: ${{ inputs.scope }}
@@ -18,6 +18,23 @@ runs:
   using: composite
   steps:
     - uses: actions/cache/restore@v5
+      if: inputs.scope == 'android'
+      id: cache-android
+      with:
+        path: |
+          .gradle
+          build
+          app/shared/build
+          app/android/build
+          utils/shared/build
+          utils/android/build
+        key: gradle-build-${{ runner.os }}-${{ runner.arch }}-v2-${{ inputs.scope }}-${{ hashFiles('gradle/libs.versions.toml', 'settings.gradle.kts', 'gradle.properties', 'build.gradle.kts', 'app/desktop/build.gradle.kts', 'app/desktop/proguard-rules.pro', 'app/shared/build.gradle.kts', 'app/android/build.gradle.kts', 'utils/shared/build.gradle.kts', 'utils/android/build.gradle.kts') }}
+        restore-keys: |
+          gradle-build-${{ runner.os }}-${{ runner.arch }}-v2-${{ inputs.scope }}-
+          gradle-build-${{ runner.os }}-${{ runner.arch }}-v2-build-jar-
+          gradle-build-${{ runner.os }}-${{ runner.arch }}-v2-
+    - uses: actions/cache/restore@v5
+      if: inputs.scope != 'android'
       id: cache
       with:
         path: |