ci: replace nonexistent artifact download with fresh build for eval job

Author: Aegis AI Assistant

.github/workflows/ci.yml

@@ -190,19 +190,25 @@ jobs:
         with:
           submodules: recursive
 
-      - name: Setup Swift
-        uses: swift-actions/setup-swift@v2
-        with:
-          swift-version: "6.0"
-      
-      - name: Download SwiftLM executable
-        uses: actions/download-artifact@v4
+      - name: Install Metal Toolchain
+        run: xcodebuild -downloadComponent MetalToolchain || true
+
+      - name: Cache Swift packages
+        uses: actions/cache@v4
         with:
-          name: SwiftLM-macOS
-          path: .build/release/
-      
-      - name: Make executable
-        run: chmod +x .build/release/SwiftLM
+          path: .build
+          key: ${{ runner.os }}-spm-SwiftLM-v2-${{ hashFiles('Package.resolved') }}
+          restore-keys: |
+            ${{ runner.os }}-spm-SwiftLM-v2-
+
+      - name: Clear stale module cache
+        run: find .build -type d -name ModuleCache -exec rm -rf {} + 2>/dev/null || true
+
+      - name: Resolve dependencies
+        run: swift package resolve
+
+      - name: Build (Release)
+        run: swift build -c release
 
       - name: Install MLX Metal library
         run: |