Make beta release artifacts reproducible on Linux and Android

Constraint: SRS-118 and SRS-119 require a Linux release package and an Android release AAB, and the current workspace also needs the sibling oboe-rs checkout for Cargo manifest loading.
Rejected: Keep release packaging as ad-hoc local knowledge | CI and contributors would still miss the required artifacts and hit the missing oboe-rs prerequisite.
Confidence: medium
Scope-risk: moderate
Directive: If the oboe-rs fork path changes or is vendored, update the helper scripts and workflow checkout steps together.
Tested: bash -n tools/build-linux-deb.sh tools/build-android-aab.sh; python3 YAML parse for .github/workflows/ci.yml, .github/workflows/bench-advisory.yml, .github/workflows/bench-baseline-update.yml; git diff --check
Not-tested: End-to-end flutter build linux --release; end-to-end flutter build appbundle --release; GitHub Actions runtime execution

.github/workflows/ci.yml

@@ -11,6 +11,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Checkout oboe-rs fork
+        run: git clone --depth 1 https://github.com/edisonjwa/oboe-rs.git ../oboe-rs
       - name: System deps (cpal / Opus / SQLite)
         run: |
           sudo apt-get update
@@ -38,6 +40,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Checkout oboe-rs fork
+        run: git clone --depth 1 https://github.com/edisonjwa/oboe-rs.git ../oboe-rs
       - uses: EmbarkStudios/cargo-deny-action@v2
         with:
           command: check
@@ -51,6 +55,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Checkout oboe-rs fork
+        run: git clone --depth 1 https://github.com/edisonjwa/oboe-rs.git ../oboe-rs
       - uses: dtolnay/rust-toolchain@stable
       - uses: Swatinem/rust-cache@v2
       - name: Install cargo-about
@@ -113,12 +119,71 @@ jobs:
     runs-on: macos-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Checkout oboe-rs fork
+        run: git clone --depth 1 https://github.com/edisonjwa/oboe-rs.git ../oboe-rs
       - uses: subosito/flutter-action@v2
         with:
           channel: stable
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
       - name: flutter pub get
         working-directory: apps/chanora_flutter
         run: flutter pub get
       - name: flutter build ios --no-codesign
         working-directory: apps/chanora_flutter
         run: flutter build ios --release --no-codesign
+
+  flutter-linux-release-package:
+    name: flutter Linux release package (.deb)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Checkout oboe-rs fork
+        run: git clone --depth 1 https://github.com/edisonjwa/oboe-rs.git ../oboe-rs
+      - name: System deps (Flutter Linux + audio + packaging)
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y \
+            clang cmake ninja-build pkg-config libgtk-3-dev liblzma-dev \
+            libasound2-dev libpulse-dev libopus-dev libsdl2-dev
+      - uses: subosito/flutter-action@v2
+        with:
+          channel: stable
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
+      - name: Build Linux .deb package
+        run: ./tools/build-linux-deb.sh
+      - name: Upload Linux package artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: chanora-linux-deb
+          path: dist/linux/*.deb
+
+  flutter-android-release-aab:
+    name: flutter Android release AAB
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Checkout oboe-rs fork
+        run: git clone --depth 1 https://github.com/edisonjwa/oboe-rs.git ../oboe-rs
+      - uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '17'
+      - uses: android-actions/setup-android@v3
+      - uses: subosito/flutter-action@v2
+        with:
+          channel: stable
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          targets: aarch64-linux-android,x86_64-linux-android
+      - uses: Swatinem/rust-cache@v2
+      - name: Install cargo-ndk
+        run: cargo install --locked cargo-ndk
+      - name: Build Android release AAB
+        run: ./tools/build-android-aab.sh
+      - name: Upload Android bundle artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: chanora-android-aab
+          path: dist/android/*.aab