Use docker/bake-action to share base layer across images

Replace the matrix strategy with docker/bake-action, which builds all three targets (vws, vwq, target-manager) in a single invocation. This allows the shared base stage to be built once instead of three times, improving build performance on multi-platform releases.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

Author: adamtheturtle

.github/workflows/release.yml

@@ -135,20 +135,10 @@ jobs:
           verbose: true
 
   docker:
-    name: Publish Docker image (${{ matrix.image.target }})
+    name: Publish Docker images
     needs: release
     runs-on: ubuntu-latest
 
-    strategy:
-      matrix:
-        image:
-          - target: target-manager
-            repo: adamtheturtle/vuforia-target-manager-mock
-          - target: vws
-            repo: adamtheturtle/vuforia-vws-mock
-          - target: vwq
-            repo: adamtheturtle/vuforia-vwq-mock
-
     permissions: {}
 
     steps:
@@ -169,13 +159,9 @@ jobs:
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v3
 
-      - name: Build and push Docker image
-        uses: docker/build-push-action@v6.19.2
+      - name: Build and push Docker images
+        uses: docker/bake-action@v6.10.0
         with:
-          file: src/mock_vws/_flask_server/Dockerfile
-          platforms: linux/amd64,linux/arm64
           push: true
-          target: ${{ matrix.image.target }}
-          tags: |-
-            ${{ matrix.image.repo }}:latest
-            ${{ matrix.image.repo }}:${{ needs.release.outputs.version }}
+        env:
+          VERSION: ${{ needs.release.outputs.version }}

docker-bake.hcl

@@ -0,0 +1,39 @@
+variable "VERSION" {
+  default = "latest"
+}
+
+group "default" {
+  targets = ["vws", "vwq", "target-manager"]
+}
+
+target "_base" {
+  dockerfile = "src/mock_vws/_flask_server/Dockerfile"
+  platforms  = ["linux/amd64", "linux/arm64"]
+}
+
+target "vws" {
+  inherits = ["_base"]
+  target   = "vws"
+  tags = [
+    "adamtheturtle/vuforia-vws-mock:latest",
+    "adamtheturtle/vuforia-vws-mock:${VERSION}",
+  ]
+}
+
+target "vwq" {
+  inherits = ["_base"]
+  target   = "vwq"
+  tags = [
+    "adamtheturtle/vuforia-vwq-mock:latest",
+    "adamtheturtle/vuforia-vwq-mock:${VERSION}",
+  ]
+}
+
+target "target-manager" {
+  inherits = ["_base"]
+  target   = "target-manager"
+  tags = [
+    "adamtheturtle/vuforia-target-manager-mock:latest",
+    "adamtheturtle/vuforia-target-manager-mock:${VERSION}",
+  ]
+}