fix: configure ccache after cache restore to prevent stale config

Same ordering bug as Conan profile (Session 8) - ccache config was being
created in workflow BEFORE cache restore, causing cached ccache.conf to
overwrite fresh configuration.

Changes:
- Build action: Add ccache config inputs (max_size, hash_dir, compiler_check)
- Build action: Configure ccache AFTER cache restore (overwrites cached config)
- Build action: Add "Show ccache config before build" step (debugging aid)
- Build action: Remove debug steps (past debugging phase)
- Build action: Remove ninja -v flag (past debugging phase)
- Nix workflow: Remove "Configure ccache" step (now handled in build action)
- macOS workflow: Remove "Configure ccache" step (now handled in build action)
- macOS workflow: Add missing stdlib and AWS credentials to build step
- Delete unused xahau-configure-ccache action (logic moved to build action)

Flow now matches Conan pattern:
1. Restore cache (includes potentially stale config)
2. Configure ccache (overwrites with fresh config: 2G max, hash_dir=true, compiler_check=content)
3. Show config (verification)
4. Build

This ensures fresh ccache configuration for each job, preventing issues
from cached config files with different settings.

.github/actions/xahau-configure-ccache/action.yml

@@ -1,45 +0,0 @@
-name: 'Configure ccache'
-description: 'Sets up ccache with consistent configuration'
-
-inputs:
-  cache_dir:
-    description: 'Path to ccache directory'
-    required: false
-    default: '~/.ccache'
-  max_size:
-    description: 'Maximum cache size'
-    required: false
-    default: '2G'
-  hash_dir:
-    description: 'Whether to include directory paths in hash'
-    required: false
-    default: 'true'
-  compiler_check:
-    description: 'How to check compiler for changes'
-    required: false
-    default: 'content'
-
-runs:
-  using: 'composite'
-  steps:
-    - name: Configure ccache
-      shell: bash
-      run: |
-        # Use ccache's default cache_dir (~/.ccache) - don't override it
-        # This avoids tilde expansion issues when setting it explicitly
-
-        # Create cache directory using ccache's default
-        mkdir -p ~/.ccache
-
-        # Configure ccache settings (but NOT cache_dir - use default)
-        ccache --set-config=max_size=${{ inputs.max_size }}
-        ccache --set-config=hash_dir=${{ inputs.hash_dir }}
-        ccache --set-config=compiler_check=${{ inputs.compiler_check }}
-
-        # Note: Not setting CCACHE_DIR - let ccache use its default (~/.ccache)
-
-        # Print config for verification
-        ccache -p
-
-        # Zero statistics before the build
-        ccache -z

.github/actions/xahau-ga-build/action.yml

@@ -47,6 +47,18 @@ inputs:
     description: 'GCC version to use for Clang toolchain (e.g. 11, 13)'
     required: false
     default: ''
+  ccache_max_size:
+    description: 'Maximum ccache size'
+    required: false
+    default: '2G'
+  ccache_hash_dir:
+    description: 'Whether to include directory paths in hash'
+    required: false
+    default: 'true'
+  ccache_compiler_check:
+    description: 'How to check compiler for changes'
+    required: false
+    default: 'content'
   aws-access-key-id:
     description: 'AWS Access Key ID for S3 cache storage'
     required: true
@@ -79,6 +91,31 @@ runs:
         aws-access-key-id: ${{ inputs.aws-access-key-id }}
         aws-secret-access-key: ${{ inputs.aws-secret-access-key }}
 
+    - name: Configure ccache
+      if: inputs.ccache_enabled == 'true'
+      shell: bash
+      run: |
+        # Use ccache's default cache_dir (~/.ccache) - don't override it
+        # This avoids tilde expansion issues when setting it explicitly
+
+        # Create cache directory using ccache's default
+        mkdir -p ~/.ccache
+
+        # Configure ccache settings (but NOT cache_dir - use default)
+        # This overwrites any cached config to ensure fresh configuration
+        ccache --set-config=max_size=${{ inputs.ccache_max_size }}
+        ccache --set-config=hash_dir=${{ inputs.ccache_hash_dir }}
+        ccache --set-config=compiler_check=${{ inputs.ccache_compiler_check }}
+
+        # Note: Not setting CCACHE_DIR - let ccache use its default (~/.ccache)
+
+        # Print config for verification
+        echo "=== ccache configuration ==="
+        ccache -p
+
+        # Zero statistics before the build
+        ccache -z
+
     - name: Configure project
       shell: bash
       run: |
@@ -157,30 +194,21 @@ runs:
           -DCMAKE_TOOLCHAIN_FILE:FILEPATH=${TOOLCHAIN_FILE} \
           -DCMAKE_BUILD_TYPE=${{ inputs.configuration }}
 
+    - name: Show ccache config before build
+      if: inputs.ccache_enabled == 'true'
+      shell: bash
+      run: |
+        echo "=========================================="
+        echo "ccache configuration before build"
+        echo "=========================================="
+        ccache -p
+        echo ""
+
     - name: Build project
       shell: bash
       run: |
         cd ${{ inputs.build_dir }}
-        # TEMPORARY: Add -v to see compile commands for ccache debugging
-        cmake --build . --config ${{ inputs.configuration }} --parallel $(nproc) -- -v
-
-    - name: Debug ccache directory
-      if: inputs.ccache_enabled == 'true'
-      shell: bash
-      run: |
-        echo "=== ccache directory contents ==="
-        ls -laR ~/.ccache || echo "Directory doesn't exist"
-        echo ""
-        echo "=== Disk space ==="
-        df -h ~
-        echo ""
-        echo "=== ccache config ==="
-        ccache --show-config | head -30
-        echo ""
-        echo "=== Directory sizes ==="
-        du -sh ~/.ccache 2>/dev/null || echo "No directory"
-        find ~/.ccache -type f -name "*.conf" -o -type f ! -name "*.conf" 2>/dev/null | head -20 || true
-        echo ""
+        cmake --build . --config ${{ inputs.configuration }} --parallel $(nproc)
 
     - name: Show ccache statistics
       if: inputs.ccache_enabled == 'true'

.github/workflows/xahau-ga-macos.yml.disabled

@@ -78,14 +78,6 @@ jobs:
       - name: Install ccache
         run: brew install ccache
 
-      - name: Configure ccache
-        uses: ./.github/actions/xahau-configure-ccache
-        with:
-          max_size: 2G
-          hash_dir: true
-          compiler_check: content
-          is_main_branch: ${{ github.ref_name == env.MAIN_BRANCH_NAME }}
-
       - name: Check environment
         run: |
           echo "PATH:"
@@ -130,6 +122,9 @@ jobs:
           compiler-id: clang
           cache_version: ${{ env.CACHE_VERSION }}
           main_branch: ${{ env.MAIN_BRANCH_NAME }}
+          stdlib: libcxx
+          aws-access-key-id: ${{ secrets.XAHAUD_GITHUB_ACTIONS_CACHE_NIQ_AWS_KEY_ID }}
+          aws-secret-access-key: ${{ secrets.XAHAUD_GITHUB_ACTIONS_CACHE_NIQ_AWS_ACCESS_KEY }}
 
       - name: Test
         run: |

.github/workflows/xahau-ga-nix.yml

@@ -231,13 +231,6 @@ jobs:
           # Install Conan 2
           pip install --upgrade "conan>=2.0,<3"
 
-      - name: Configure ccache
-        uses: ./.github/actions/xahau-configure-ccache
-        with:
-          max_size: 2G
-          hash_dir: true
-          compiler_check: content
-
       - name: Check environment
         run: |
           echo "PATH:"