feat: implement Havenllo single-board kanban (Go+SQLite backend, Preact/Vite frontend)

- Single fixed 'Haven' board: lists (To do/In progress/Done) + cards, no multi-board
- Go 1.24 backend, CGO-free modernc.org/sqlite, embedded SPA, REST /api
- Preact + Vite + TS frontend, native HTML5 drag-and-drop, optimistic UI, dark Haven theme
- PVC (nfs-client) for SQLite, root container on NFS, simple nginx ingress havenllo.haven
- Dockerfile multi-arch build, Gitea CI via pipeline-actions@main

deploy/havenllo.yaml

@@ -0,0 +1,120 @@
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: havenllo-data
+  namespace: default
+  annotations:
+    nfs.io/storage-path: havenllo-data
+spec:
+  accessModes:
+    - ReadWriteOnce
+  storageClassName: nfs-client
+  resources:
+    requests:
+      storage: 1Gi
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: havenllo
+  namespace: default
+  labels:
+    app.kubernetes.io/name: havenllo
+spec:
+  replicas: 1
+  strategy:
+    type: Recreate
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: havenllo
+  template:
+    metadata:
+      labels:
+        app.kubernetes.io/name: havenllo
+    spec:
+      containers:
+        - name: havenllo
+          image: git.ivanch.me/ivanch/havenllo:latest
+          imagePullPolicy: Always
+          ports:
+            - name: http
+              containerPort: 8080
+              protocol: TCP
+          env:
+            - name: HAVENLLO_DATABASE_PATH
+              value: /data/havenllo.db
+            - name: HAVENLLO_LISTEN_ADDR
+              value: :8080
+          volumeMounts:
+            - name: data
+              mountPath: /data
+          resources:
+            requests:
+              cpu: 50m
+              memory: 64Mi
+            limits:
+              cpu: 500m
+              memory: 256Mi
+          readinessProbe:
+            httpGet:
+              path: /api/health
+              port: http
+            initialDelaySeconds: 2
+            periodSeconds: 5
+            timeoutSeconds: 2
+            failureThreshold: 3
+          livenessProbe:
+            httpGet:
+              path: /api/health
+              port: http
+            initialDelaySeconds: 10
+            periodSeconds: 10
+            timeoutSeconds: 2
+            failureThreshold: 3
+          securityContext:
+            runAsUser: 0
+            allowPrivilegeEscalation: false
+            readOnlyRootFilesystem: true
+            capabilities:
+              drop:
+                - ALL
+      volumes:
+        - name: data
+          persistentVolumeClaim:
+            claimName: havenllo-data
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: havenllo
+  namespace: default
+  labels:
+    app.kubernetes.io/name: havenllo
+spec:
+  type: ClusterIP
+  selector:
+    app.kubernetes.io/name: havenllo
+  ports:
+    - name: http
+      port: 8080
+      targetPort: 8080
+      protocol: TCP
+---
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: havenllo
+  namespace: default
+spec:
+  ingressClassName: nginx
+  rules:
+    - host: havenllo.haven
+      http:
+        paths:
+          - path: /
+            pathType: Prefix
+            backend:
+              service:
+                name: havenllo
+                port:
+                  number: 8080