build: server cache improvements

.github/workflows/docker-build.yml

@@ -57,6 +57,9 @@ jobs:
           # Copy built admin UI to public directory
           cp -r packages/admin-ui/build lamassu-server/public
           
+          # Copy Dockerfile to lamassu-server context
+          cp build/server.Dockerfile lamassu-server/
+          
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 
@@ -69,17 +72,21 @@ jobs:
       - name: Build and push server image
         uses: docker/build-push-action@v5
         with:
-          context: .
+          context: lamassu-server
           push: true
           target: l-s
-          file: ./build/server.Dockerfile
+          file: lamassu-server/server.Dockerfile
           tags: ${{ env.DOCKERHUB_SERVER_REPO }}:latest
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
 
       - name: Build and push admin server image
         uses: docker/build-push-action@v5
         with:
-          context: .
+          context: lamassu-server
           push: true
           target: l-a-s
-          file: ./build/server.Dockerfile
+          file: lamassu-server/server.Dockerfile
           tags: ${{ env.DOCKERHUB_ADMIN_REPO }}:latest
+          cache-from: type=gha
+          cache-to: type=gha,mode=max