ci: replace sccache with Swatinem/rust-cache for improved stability (#227)

Remove mozilla-actions/sccache-action which was causing frequent crashes
in CI/CD pipelines. Replace it with Swatinem/rust-cache@v2 which provides:

- Better stability and reliability
- Similar performance via intelligent incremental caching
- Simpler configuration without wrapper setup
- No RUSTC_WRAPPER or separate registry caching needed

This change affects both CI and Release workflows, replacing all sccache
setup steps with the rust-cache action.

Co-authored-by: Droid Agent <droid@factory.ai>

Author: echobt

.github/workflows/ci.yml

@@ -15,9 +15,6 @@ env:
   CARGO_REGISTRIES_CRATES_IO_PROTOCOL: sparse
   # Incremental compilation off for CI (more reproducible, better caching)
   CARGO_INCREMENTAL: 0
-  # Use sccache for shared compilation cache
-  SCCACHE_GHA_ENABLED: "true"
-  RUSTC_WRAPPER: "sccache"
 
 # Ensure only one CI run per branch at a time
 concurrency:
@@ -75,28 +72,11 @@ jobs:
         with:
           components: clippy
 
-      - name: Setup sccache
-        uses: mozilla-actions/sccache-action@v0.0.6
-      
-      - name: Cache cargo registry & git
-        uses: actions/cache@v4
-        with:
-          path: |
-            ~/.cargo/registry/index/
-            ~/.cargo/registry/cache/
-            ~/.cargo/git/db/
-          key: cargo-registry-${{ needs.setup-cache.outputs.cache-key }}
-          restore-keys: |
-            cargo-registry-
-      
-      - name: Cache cargo build
-        uses: actions/cache@v4
+      - name: Setup Rust cache
+        uses: Swatinem/rust-cache@v2
         with:
-          path: target/
-          key: cargo-build-clippy-${{ runner.os }}-${{ needs.setup-cache.outputs.cache-key }}
-          restore-keys: |
-            cargo-build-clippy-${{ runner.os }}-
-            cargo-build-${{ runner.os }}-
+          prefix-key: "rust-clippy"
+          shared-key: ${{ needs.setup-cache.outputs.cache-key }}
 
       - name: Run clippy
         run: cargo +nightly clippy --workspace --all-targets --all-features --exclude cortex-gui -- -D warnings
@@ -130,28 +110,11 @@ jobs:
       - name: Install Rust nightly
         uses: dtolnay/rust-toolchain@nightly
 
-      - name: Setup sccache
-        uses: mozilla-actions/sccache-action@v0.0.6
-      
-      - name: Cache cargo registry & git
-        uses: actions/cache@v4
-        with:
-          path: |
-            ~/.cargo/registry/index/
-            ~/.cargo/registry/cache/
-            ~/.cargo/git/db/
-          key: cargo-registry-${{ needs.setup-cache.outputs.cache-key }}
-          restore-keys: |
-            cargo-registry-
-      
-      - name: Cache cargo build
-        uses: actions/cache@v4
+      - name: Setup Rust cache
+        uses: Swatinem/rust-cache@v2
         with:
-          path: target/
-          key: cargo-build-test-${{ matrix.name }}-${{ needs.setup-cache.outputs.cache-key }}
-          restore-keys: |
-            cargo-build-test-${{ matrix.name }}-
-            cargo-build-${{ matrix.name }}-
+          prefix-key: "rust-test-${{ matrix.name }}"
+          shared-key: ${{ needs.setup-cache.outputs.cache-key }}
 
       - name: Run tests
         run: cargo +nightly test --workspace --all-features --exclude cortex-gui
@@ -187,28 +150,11 @@ jobs:
       - name: Install Rust nightly
         uses: dtolnay/rust-toolchain@nightly
 
-      - name: Setup sccache
-        uses: mozilla-actions/sccache-action@v0.0.6
-      
-      - name: Cache cargo registry & git
-        uses: actions/cache@v4
-        with:
-          path: |
-            ~/.cargo/registry/index/
-            ~/.cargo/registry/cache/
-            ~/.cargo/git/db/
-          key: cargo-registry-${{ needs.setup-cache.outputs.cache-key }}
-          restore-keys: |
-            cargo-registry-
-      
-      - name: Cache cargo build
-        uses: actions/cache@v4
+      - name: Setup Rust cache
+        uses: Swatinem/rust-cache@v2
         with:
-          path: target/
-          key: cargo-build-check-${{ matrix.name }}-${{ needs.setup-cache.outputs.cache-key }}
-          restore-keys: |
-            cargo-build-check-${{ matrix.name }}-
-            cargo-build-${{ matrix.name }}-
+          prefix-key: "rust-build-${{ matrix.name }}"
+          shared-key: ${{ needs.setup-cache.outputs.cache-key }}
 
       - name: Check build
         run: cargo +nightly check --workspace --all-features --exclude cortex-gui
@@ -268,28 +214,11 @@ jobs:
       - name: Install Rust nightly
         uses: dtolnay/rust-toolchain@nightly
 
-      - name: Setup sccache
-        uses: mozilla-actions/sccache-action@v0.0.6
-      
-      - name: Cache cargo registry & git
-        uses: actions/cache@v4
-        with:
-          path: |
-            ~/.cargo/registry/index/
-            ~/.cargo/registry/cache/
-            ~/.cargo/git/db/
-          key: cargo-registry-${{ needs.setup-cache.outputs.cache-key }}
-          restore-keys: |
-            cargo-registry-
-      
-      - name: Cache cargo build (GUI)
-        uses: actions/cache@v4
+      - name: Setup Rust cache
+        uses: Swatinem/rust-cache@v2
         with:
-          path: target/
-          key: cargo-build-gui-${{ matrix.name }}-${{ needs.setup-cache.outputs.cache-key }}
-          restore-keys: |
-            cargo-build-gui-${{ matrix.name }}-
-            cargo-build-${{ matrix.name }}-
+          prefix-key: "rust-gui-${{ matrix.name }}"
+          shared-key: ${{ needs.setup-cache.outputs.cache-key }}
 
       - name: Check GUI build
         run: cargo +nightly check -p cortex-gui

.github/workflows/release.yml

@@ -30,9 +30,6 @@ env:
   CARGO_REGISTRIES_CRATES_IO_PROTOCOL: sparse
   # Incremental compilation off for release builds
   CARGO_INCREMENTAL: 0
-  # Use sccache for shared compilation cache
-  SCCACHE_GHA_ENABLED: "true"
-  RUSTC_WRAPPER: "sccache"
 
 permissions:
   contents: write
@@ -155,27 +152,11 @@ jobs:
           echo '[target.aarch64-unknown-linux-gnu]' >> ~/.cargo/config.toml
           echo 'linker = "aarch64-linux-gnu-gcc"' >> ~/.cargo/config.toml
 
-      - name: Setup sccache
-        uses: mozilla-actions/sccache-action@v0.0.6
-
-      - name: Cache cargo registry & git
-        uses: actions/cache@v4
+      - name: Setup Rust cache
+        uses: Swatinem/rust-cache@v2
         with:
-          path: |
-            ~/.cargo/registry/index/
-            ~/.cargo/registry/cache/
-            ~/.cargo/git/db/
-          key: cargo-registry-${{ needs.prepare.outputs.cache_key }}
-          restore-keys: |
-            cargo-registry-
-
-      - name: Cache cargo build
-        uses: actions/cache@v4
-        with:
-          path: target/
-          key: cargo-release-cli-${{ matrix.target }}-${{ needs.prepare.outputs.cache_key }}
-          restore-keys: |
-            cargo-release-cli-${{ matrix.target }}-
+          prefix-key: "rust-release-cli-${{ matrix.target }}"
+          shared-key: ${{ needs.prepare.outputs.cache_key }}
 
       - name: Build release binary
         run: cargo +nightly build --release --target ${{ matrix.target }} -p cortex-cli
@@ -272,29 +253,14 @@ jobs:
             libgtk-3-dev \
             libayatana-appindicator3-dev
 
-      - name: Setup sccache
-        uses: mozilla-actions/sccache-action@v0.0.6
-
-      - name: Cache cargo registry & git
-        uses: actions/cache@v4
-        with:
-          path: |
-            ~/.cargo/registry/index/
-            ~/.cargo/registry/cache/
-            ~/.cargo/git/db/
-          key: cargo-registry-${{ needs.prepare.outputs.cache_key }}
-          restore-keys: |
-            cargo-registry-
-
-      - name: Cache cargo build (GUI)
-        uses: actions/cache@v4
+      - name: Setup Rust cache
+        uses: Swatinem/rust-cache@v2
         with:
-          path: |
-            target/
-            cortex-gui/src-tauri/target/
-          key: cargo-release-gui-${{ matrix.target }}-${{ needs.prepare.outputs.cache_key }}
-          restore-keys: |
-            cargo-release-gui-${{ matrix.target }}-
+          prefix-key: "rust-release-gui-${{ matrix.target }}"
+          shared-key: ${{ needs.prepare.outputs.cache_key }}
+          workspaces: |
+            .
+            cortex-gui/src-tauri
 
       - name: Cache pnpm
         uses: actions/cache@v4