feat: initial tictactoe web app with CI/CD pipeline

- Express app serving vanilla JS 2-player TicTacToe game
- Dockerfile (multi-stage node:18-slim)
- Jenkinsfile (K8s pod: test → Harbor push → Helm bump → Gitea push)
- Helm chart v1.0.0 with HTTPRoute for tictactoe.fireflylab.local

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

manifest/helm/values.yaml

@@ -0,0 +1,10 @@
+image:
+  repository: harbor.fireflylab.local/library/tictactoe
+  tag: latest
+  pullPolicy: IfNotPresent
+
+replicaCount: 1
+
+service:
+  port: 80
+  targetPort: 3000