ci: build node ARM64 images in parallel [CI] [SKIP TESTS]

.woodpecker/dev-image.yml

@@ -68,7 +68,7 @@ steps:
       - bash ci/build-dev-image.sh probe
     depends_on: []
 
-  # Build ARM64 only after the amd64 set; Agent and Probe can then build in parallel.
+  # Build both node architectures in parallel; each multi-architecture index waits for both of its images.
   - name: build-linux-arm64-agent
     image: bash
     environment:
@@ -82,10 +82,7 @@ steps:
         from_secret: release_signing_key
     commands:
       - bash ci/build-dev-image.sh agent arm64
-    depends_on:
+    depends_on: []
-      - build-linux-amd64-backend
-      - build-linux-amd64-agent
-      - build-linux-amd64-probe
 
   - name: build-linux-arm64-probe
     image: bash
@@ -100,10 +97,7 @@ steps:
         from_secret: release_signing_key
     commands:
       - bash ci/build-dev-image.sh probe arm64
-    depends_on:
+    depends_on: []
-      - build-linux-amd64-backend
-      - build-linux-amd64-agent
-      - build-linux-amd64-probe
 
   - name: publish-linux-agent-multiarch
     image: bash