ci: trigger stage build on PRs (deploy only on merge)

.gitea/workflows/stage.yaml

@@ -14,6 +14,16 @@ on:
       - 'build-stage.sh'
       - '.gitea/workflows/stage.yaml'
 
+  pull_request:
+    branches: [stage]
+    paths:
+      - 'src/**'
+      - 'dist/**'
+      - 'runtime/**'
+      - 'Dockerfile.stage'
+      - 'build-stage.sh'
+      - '.gitea/workflows/stage.yaml'
+
   workflow_dispatch:
     inputs:
       tag:
@@ -134,13 +144,13 @@ jobs:
           docker tag "marketing:${{ steps.tag.outputs.tag }}" "us-central1-docker.pkg.dev/neuron-785695/neuron-marketing/marketing:stage-latest"
 
       - name: Push image
-        if: steps.changetype.outputs.asset_only != 'true'
+        if: steps.changetype.outputs.asset_only != 'true' && github.event_name != 'pull_request'
         run: |
           docker push "${{ steps.tag.outputs.image }}"
           docker push "us-central1-docker.pkg.dev/neuron-785695/neuron-marketing/marketing:stage-latest"
 
       - name: Asset-only fast build
-        if: steps.changetype.outputs.asset_only == 'true'
+        if: steps.changetype.outputs.asset_only == 'true' && github.event_name != 'pull_request'
         env:
           IMAGE: ${{ steps.tag.outputs.image }}
         run: |
@@ -165,6 +175,7 @@ jobs:
           echo "Fast asset build complete"
 
       - name: Deploy to marketing-stage
+        if: github.event_name != 'pull_request'
         id: deploy-stage
         env:
           IMAGE: ${{ steps.tag.outputs.image }}
@@ -193,6 +204,7 @@ jobs:
             --quiet
 
       - name: Smoke test stage
+        if: github.event_name != 'pull_request'
         run: |
           set -euo pipefail
           STAGE_URL="${{ steps.deploy-stage.outputs.stage_url }}"