ci: add Woodpecker CI pipeline for Zot registry build and k3s deploy

.woodpecker.yml

@@ -0,0 +1,29 @@
+# StemeDB CI/CD Pipeline
+# Push to main → Kaniko builds amd64 image → pushes to registry.threesix.ai → kubectl deploy
+when:
+  branch: main
+  event: push
+
+steps:
+  build:
+    image: woodpeckerci/plugin-kaniko
+    settings:
+      registry: registry.threesix.ai
+      repo: registry.threesix.ai/stemedb-api
+      tags:
+        - latest
+        - ${CI_COMMIT_SHA:0:8}
+      context: .
+      dockerfile: Dockerfile
+      cache: true
+      cache_repo: registry.threesix.ai/stemedb-api/cache
+      skip_tls_verify: true
+
+  deploy:
+    image: bitnami/kubectl:latest
+    commands:
+      - mkdir -p ~/.kube && echo "$KUBECONFIG" > ~/.kube/config
+      - kubectl set image deployment/stemedb-api stemedb-api=registry.threesix.ai/stemedb-api:${CI_COMMIT_SHA:0:8} -n stemedb
+      - kubectl rollout status deployment/stemedb-api -n stemedb --timeout=300s
+    secrets: [kubeconfig]
+    depends_on: [build]