Add complete webhook-based CI/CD with automatic builds and notifications

This commit implements a full webhook-triggered CI/CD pipeline:

**Flux Components:**
- Flux Receiver for Gitea webhooks (generic type, NodePort 30090)
- Notification Provider for notify.caffeinetux.com
- Alerts for git updates, builds, and deployments

**Build Automation:**
- Webhook listener deployment that triggers on git push
- Automatic Kaniko build jobs with git metadata
- Images tagged with both 'latest' and commit SHA
- Build notifications sent at start and completion

**Workflow:**
1. Push to Gitea → Webhooks trigger Flux receiver & build listener
2. Build listener creates Kaniko job with commit info
3. Kaniko builds and pushes to Harbor (latest + SHA tags)
4. Flux auto-deploys latest image to cluster
5. Notifications sent to notify.caffeinetux.com at each stage

**Configuration:**
- Token: APMvTuncQJmm6vd
- Webhook path: /hook/548969c2b24c717fe9e5af8c78ddfeec40d3024c270c7e85ac8f986259aeec9a
- Build trigger: http://<node-ip>:30091/webhook
- Comprehensive setup documentation in WEBHOOK_SETUP_GUIDE.md

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

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

flux-notification-provider.yaml

@@ -0,0 +1,20 @@
+---
+apiVersion: v1
+kind: Secret
+metadata:
+  name: notify-token
+  namespace: flux-system
+type: Opaque
+stringData:
+  token: "APMvTuncQJmm6vd"
+---
+apiVersion: notification.toolkit.fluxcd.io/v1beta3
+kind: Provider
+metadata:
+  name: neon-vortex-notify
+  namespace: flux-system
+spec:
+  type: generic
+  address: https://notify.caffeinetux.com
+  secretRef:
+    name: notify-token