ci: add ccache/sccache compilation caching to speed up CI builds (#360)

* ci: add ccache/sccache compilation caching to speed up CI builds

- Use hendrikmuhs/ccache-action@v1.2 for Linux/macOS/iOS/Android/clang-tidy
  (auto-installs ccache, manages cache, sets env vars, shows stats)
- Use mozilla-actions/sccache-action@v0.0.9 for Windows (MSVC compatible)
- Add CMAKE_C/CXX_COMPILER_LAUNCHER to all CMake build steps
- Exclude wheel build and nightly coverage workflows per decision

* ci: switch MacOS & Linux build from Unix Makefiles to Ninja generator

- Replace CMAKE_GENERATOR='Unix Makefiles' with 'Ninja' in pip build
- Replace 'make unittest -j' with 'cmake --build --target unittest --parallel'
- Add '-G Ninja' to C++ and C example cmake configure steps
- Replace 'make -j' with 'cmake --build --parallel' for examples
- Aligns with Windows and Android workflows which already use Ninja

* ci: enable parallel ctest execution with -j and --timeout

- Use CMake ProcessorCount module to detect available CPU cores
- Add -j ${NPROC} to ctest command for parallel test execution
- Add --timeout 300 to prevent individual tests from hanging CI
- Fallback to NPROC=1 when ProcessorCount returns 0
- iOS target unchanged (build-only, no test execution)

* Revert "ci: enable parallel ctest execution with -j and --timeout"

This reverts commit d196dac5f17b1f7cae443360c88bbd8c935dc145.

* fix(ci): remove sccache from Windows, fix cmake.define quote issues

Windows (05-windows-build.yml):
- Remove mozilla-actions/sccache-action: sccache incompatible with MSVC /FS flag
- Remove SCCACHE_GHA_ENABLED env var
- Remove CMAKE_C/CXX_COMPILER_LAUNCHER=sccache from build steps
- Remove 'Show sccache statistics' step
- MSVC /FS (global PDB concurrency flag) causes fatal C1041 when used with sccache

MacOS & Linux (03-macos-linux-build.yml):
- Fix cmake.define values: remove extra quotes around 'ccache' and 'ON'
- Bare values required: cmake.define.FOO=bar not cmake.define.FOO="bar"

* feat: cache key with platform and os

* ci: add compiler to ccache key to avoid cache pollution

* ci: optimize cache usage to reduce bloat

- Add max-size limits to all ccache configs (150M general, 300M Android,
  100M clang-tidy) to prevent unbounded cache growth
- Remove redundant iOS full build directory cache (~1.2 GB) since ccache
  already handles incremental compilation
- Fix iOS protoc cache key to use thirdparty/protobuf/** instead of
  src/**, avoiding unnecessary cache misses on business code changes

* ci: trigger CI run

.github/workflows/03-macos-linux-build.yml

@@ -40,6 +40,12 @@ jobs:
         with:
           submodules: recursive
 
+      - name: Setup ccache
+        uses: hendrikmuhs/ccache-action@v1.2
+        with:
+          key: ${{ inputs.platform }}-${{ inputs.os }}-${{ inputs.compiler || 'gcc' }}
+          max-size: 150M
+
       - name: Set up Python
         uses: actions/setup-python@v6
         with:
@@ -95,18 +101,20 @@ jobs:
         run: |
           cd "$GITHUB_WORKSPACE"
 
-          CMAKE_GENERATOR="Unix Makefiles" \
+          CMAKE_GENERATOR="Ninja" \
           CMAKE_BUILD_PARALLEL_LEVEL="$NPROC" \
           python -m pip install -v . \
             --no-build-isolation \
-            --config-settings='cmake.define.BUILD_TOOLS="ON"' \
+            --config-settings='cmake.define.BUILD_TOOLS=ON' \
+            --config-settings='cmake.define.CMAKE_C_COMPILER_LAUNCHER=ccache' \
+            --config-settings='cmake.define.CMAKE_CXX_COMPILER_LAUNCHER=ccache' \
             ${{ matrix.arch_flag }}
         shell: bash
 
       - name: Run C++ Tests
         run: |
           cd "$GITHUB_WORKSPACE/build"
-          make unittest -j$NPROC
+          cmake --build . --target unittest --parallel $NPROC
         shell: bash
 
       - name: Run Python Tests
@@ -119,8 +127,10 @@ jobs:
         run: |
           cd "$GITHUB_WORKSPACE/examples/c++"
           mkdir build && cd build
-          cmake .. -DCMAKE_BUILD_TYPE=Release
-          make -j $NPROC
+          cmake .. -G Ninja -DCMAKE_BUILD_TYPE=Release \
+            -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+            -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
+          cmake --build . --parallel $NPROC
           ./db-example
           ./core-example
           ./ailego-example
@@ -130,8 +140,10 @@ jobs:
         run: |
           cd "$GITHUB_WORKSPACE/examples/c"
           mkdir build && cd build
-          cmake .. -DCMAKE_BUILD_TYPE=Release
-          make -j $NPROC
+          cmake .. -G Ninja -DCMAKE_BUILD_TYPE=Release \
+            -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+            -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
+          cmake --build . --parallel $NPROC
           ./c_api_basic_example
           ./c_api_collection_schema_example
           ./c_api_doc_example

.github/workflows/04-android-build.yml

@@ -25,11 +25,6 @@ jobs:
       matrix:
         abi: [x86_64]
         api: ${{ github.event.inputs.api && fromJSON(format('["{0}"]', github.event.inputs.api)) || fromJSON('["34"]') }}
-    env:
-      CCACHE_BASEDIR: ${{ github.workspace }}
-      CCACHE_NOHASHDIR: '1'
-      CCACHE_SLOPPINESS: clang_index_store,file_stat_matches,include_file_mtime,locale,time_macros
-
     steps:
       # ── Environment setup ──────────────────────────────────────────────
       - name: Checkout
@@ -42,15 +37,13 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y --no-install-recommends \
             cmake ninja-build git ca-certificates python3 \
-            build-essential make ccache unzip curl
+            build-essential make unzip curl
 
-      - name: Cache ccache
-        uses: actions/cache@v5
+      - name: Setup ccache
+        uses: hendrikmuhs/ccache-action@v1.2
         with:
-          path: ~/.ccache
-          key: ${{ runner.os }}-ccache-android-${{ matrix.abi }}-${{ github.sha }}
-          restore-keys: |
-            ${{ runner.os }}-ccache-android-${{ matrix.abi }}-
+          key: android-${{ matrix.abi }}
+          max-size: 300M
 
       - name: Setup Java 17
         uses: actions/setup-java@v5

.github/workflows/06-ios-build.yml

@@ -31,29 +31,31 @@ jobs:
         with:
           submodules: recursive
 
+      - name: Setup ccache
+        uses: hendrikmuhs/ccache-action@v1.2
+        with:
+          key: ios-${{ matrix.platform }}
+          max-size: 150M
+
       - name: Cache host protoc build
         uses: actions/cache@v5
         with:
           path: build_host
-          key: macos-host-protoc-${{ hashFiles('src/**', 'CMakeLists.txt') }}
+          key: macos-host-protoc-${{ hashFiles('thirdparty/protobuf/**', 'CMakeLists.txt') }}
           restore-keys: |
             macos-host-protoc-
 
       - name: Build host protoc
         run: |
           if [ ! -f "build_host/bin/protoc" ]; then
-            cmake -S . -B build_host -DCMAKE_BUILD_TYPE=Release -DCMAKE_POLICY_VERSION_MINIMUM=3.5
+            cmake -S . -B build_host -DCMAKE_BUILD_TYPE=Release -DCMAKE_POLICY_VERSION_MINIMUM=3.5 \
+              -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+              -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
             cmake --build build_host --target protoc --parallel $(sysctl -n hw.ncpu)
           else
             echo "Using cached host protoc"
           fi
 
-      - name: Cache iOS build
-        uses: actions/cache@v5
-        with:
-          path: build_ios_${{ matrix.platform }}
-          key: ios-build-${{ matrix.platform }}-${{ hashFiles('src/**', 'CMakeLists.txt', 'cmake/**', 'thirdparty/**') }}
-
       - name: Configure and Build
         run: |
           git submodule foreach --recursive 'git stash --include-untracked' || true
@@ -72,7 +74,9 @@ jobs:
             -DCMAKE_INSTALL_PREFIX="./install" \
             -DGLOBAL_CC_PROTOBUF_PROTOC="$GITHUB_WORKSPACE/build_host/bin/protoc" \
             -DIOS=ON \
-            -DCMAKE_POLICY_VERSION_MINIMUM=3.5
+            -DCMAKE_POLICY_VERSION_MINIMUM=3.5 \
+            -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+            -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
 
           cmake --build build_ios_${{ matrix.platform }} --parallel $NPROC
 

.github/workflows/clang_tidy.yml

@@ -29,11 +29,19 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y clang-tidy=1:18.0-59~exp2 cmake ninja-build libomp-dev
 
+      - name: Setup ccache
+        uses: hendrikmuhs/ccache-action@v1.2
+        with:
+          key: clang-tidy
+          max-size: 100M
+
       - name: Configure CMake and export compile commands
         run: |
           cmake -S . -B build -G Ninja \
             -DCMAKE_EXPORT_COMPILE_COMMANDS=ON \
-            -DBUILD_TOOLS=ON
+            -DBUILD_TOOLS=ON \
+            -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+            -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
 
       - name: Collect changed C/C++ files
         id: changed_files