Add phpMyAdmin deployment manifest

- Use official phpmyadmin/phpmyadmin image (bitnami is now paid)
- Configure MySQL host to VPC internal IP (10.118.0.4)
- Allow arbitrary server connections for flexibility

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: cmyui

k8s/phpmyadmin/README.md

@@ -0,0 +1,31 @@
+# phpMyAdmin
+
+Simple phpMyAdmin deployment using the official image.
+
+## Deploy
+
+```bash
+kubectl apply -f k8s/phpmyadmin/deployment.yaml
+```
+
+## Configuration
+
+Environment variables in `deployment.yaml`:
+- `PMA_HOST`: MySQL server address (VPC internal IP: 10.118.0.4)
+- `PMA_PORT`: MySQL port (3306)
+- `PMA_ARBITRARY`: Allow connecting to any MySQL server (1 = enabled)
+
+## Access
+
+phpMyAdmin is exposed via the k8s-rev-proxy nginx configuration.
+
+For local access via port-forward:
+```bash
+kubectl port-forward svc/phpmyadmin 8080:80
+```
+Then open http://localhost:8080
+
+## Notes
+
+Previously used Bitnami Helm chart, but Bitnami moved to paid subscriptions
+in August 2025. Migrated to official `phpmyadmin/phpmyadmin` image.

k8s/phpmyadmin/deployment.yaml

@@ -0,0 +1,66 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: phpmyadmin
+  namespace: default
+  labels:
+    app: phpmyadmin
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: phpmyadmin
+  template:
+    metadata:
+      labels:
+        app: phpmyadmin
+    spec:
+      containers:
+      - name: phpmyadmin
+        image: phpmyadmin/phpmyadmin:latest
+        ports:
+        - containerPort: 80
+          name: http
+        env:
+        - name: PMA_HOST
+          value: "10.118.0.4"
+        - name: PMA_PORT
+          value: "3306"
+        - name: PMA_ARBITRARY
+          value: "1"
+        resources:
+          requests:
+            cpu: 100m
+            memory: 128Mi
+          limits:
+            cpu: 250m
+            memory: 256Mi
+        livenessProbe:
+          httpGet:
+            path: /
+            port: 80
+          initialDelaySeconds: 30
+          periodSeconds: 10
+        readinessProbe:
+          httpGet:
+            path: /
+            port: 80
+          initialDelaySeconds: 5
+          periodSeconds: 5
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: phpmyadmin
+  namespace: default
+  labels:
+    app: phpmyadmin
+spec:
+  type: ClusterIP
+  ports:
+  - port: 80
+    targetPort: 80
+    protocol: TCP
+    name: http
+  selector:
+    app: phpmyadmin