feat(ci): add downstream repository triggers (US-005)

Add trigger-downstream job that:
- Runs only on master branch and kool-dev/docker-php repo
- Waits for all push jobs to complete (nginx + node)
- Triggers 4 downstream repositories via repository-dispatch:
  - kool-dev/docker-wordpress
  - kool-dev/docker-php-sqlsrv
  - kool-dev/docker-php-swoole
  - kool-dev/docker-phpqa

Uses peter-evans/repository-dispatch@v3 with DISPATCH_TOKEN secret.

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

Author: fabriciojs

.github/workflows/ci-cd.yml

@@ -541,3 +541,33 @@ jobs:
           push: true
           platforms: linux/amd64,linux/arm64
           tags: kooldev/php:8.4-debian-nginx${{ matrix.type }}
+
+  # ===========================================
+  # DOWNSTREAM TRIGGERS (master branch only)
+  # ===========================================
+  # These jobs trigger builds in dependent repositories after all
+  # images have been successfully pushed to Docker Hub.
+
+  trigger-downstream:
+    needs:
+      - push-alpine-nginx
+      - push-alpine-node
+      - push-debian-nginx
+    if: github.ref == 'refs/heads/master' && github.repository == 'kool-dev/docker-php'
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        repo:
+          - kool-dev/docker-wordpress
+          - kool-dev/docker-php-sqlsrv
+          - kool-dev/docker-php-swoole
+          - kool-dev/docker-phpqa
+
+    steps:
+      - name: Trigger ${{ matrix.repo }}
+        uses: peter-evans/repository-dispatch@v3
+        with:
+          token: ${{ secrets.DISPATCH_TOKEN }}
+          repository: ${{ matrix.repo }}
+          event-type: docker-php-updated

tasks/prd-ci-cd-refactor.md

@@ -61,16 +61,16 @@ The core problem: multi-arch builds require the `docker-container` buildx driver
 - [x] Debian-specific tests preserved (gosu, bash)
 - [x] Supervisord test uses correct flag: `supervisord --version` (not `supervisord version`)
 
-### US-005: Downstream triggers
+### US-005: Downstream triggers ✅ COMPLETED
 **Description:** As a maintainer, I want downstream repositories to be triggered after all images are successfully pushed.
 
 **Acceptance Criteria:**
-- [ ] Triggers only run on master branch and correct repository
-- [ ] Triggers wait for ALL push jobs to complete
-- [ ] Trigger: kool-dev/docker-wordpress
-- [ ] Trigger: kool-dev/docker-php-sqlsrv
-- [ ] Trigger: kool-dev/docker-php-swoole
-- [ ] Trigger: kool-dev/docker-phpqa
+- [x] Triggers only run on master branch and correct repository
+- [x] Triggers wait for ALL push jobs to complete
+- [x] Trigger: kool-dev/docker-wordpress
+- [x] Trigger: kool-dev/docker-php-sqlsrv
+- [x] Trigger: kool-dev/docker-php-swoole
+- [x] Trigger: kool-dev/docker-phpqa
 
 ## Functional Requirements