Add complete CI/CD pipeline with Tekton and Flux image automation

- Add Tekton pipeline and triggers for automated builds on git push
- Add Flux ImageRepository to track Harbor registry images
- Add Flux ImagePolicy for semantic versioning strategy
- Add Flux ImageUpdateAutomation to auto-update HelmRelease
- Update HelmRelease with image automation marker
- Add comprehensive CI/CD pipeline setup documentation

This enables automatic build and deployment when pushing to Gitea:
1. Gitea webhook triggers Tekton pipeline
2. Kaniko builds and pushes image to Harbor
3. Flux detects new image and updates deployment
4. Application automatically deploys to cluster

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

flux-imageupdateautomation.yaml

@@ -0,0 +1,28 @@
+apiVersion: image.toolkit.fluxcd.io/v1beta2
+kind: ImageUpdateAutomation
+metadata:
+  name: neon-vortex
+  namespace: flux-system
+spec:
+  interval: 1m
+  sourceRef:
+    kind: GitRepository
+    name: neon-vortex
+    namespace: flux-system
+  git:
+    checkout:
+      ref:
+        branch: main
+    commit:
+      author:
+        email: flux@cluster.local
+        name: Flux Image Automation
+      messageTemplate: |
+        Update image to {{range .Updated.Images}}{{println .}}{{end}}
+
+        Automation: flux-system/neon-vortex
+    push:
+      branch: main
+  update:
+    path: ./flux-helmrelease.yaml
+    strategy: Setters