refactor: remove La Suite services (except Meet + Collabora), delete local overlay

La Suite Messages, Calendars, Drive, Projects, Hive, Integration, and
Postfix are replaced by Stalwart (mail) and Tuwunel (messaging). Meet
and Collabora remain for video conferencing and document editing.

Local overlay was POC only — all deployment targets production now.

Deleted: 37 La Suite manifests, Drive Helm chart, 7 local overlay files,
stale MTA-in hostPort patch. Cleaned up production image overrides and
resource patches for removed services.

base/lasuite/messages-frontend-deployment.yaml

@@ -1,53 +0,0 @@
-apiVersion: apps/v1
-kind: Deployment
-metadata:
-  name: messages-frontend
-  namespace: lasuite
-spec:
-  replicas: 1
-  selector:
-    matchLabels:
-      app: messages-frontend
-  template:
-    metadata:
-      labels:
-        app: messages-frontend
-    spec:
-      containers:
-        - name: messages-frontend
-          image: messages-frontend
-          ports:
-            - containerPort: 8080
-          env:
-            - name: MESSAGES_FRONTEND_BACKEND_SERVER
-              value: messages-backend.lasuite.svc.cluster.local:80
-            - name: PORT
-              value: "8080"
-          livenessProbe:
-            httpGet:
-              path: /
-              port: 8080
-            initialDelaySeconds: 10
-            periodSeconds: 20
-          readinessProbe:
-            httpGet:
-              path: /
-              port: 8080
-            initialDelaySeconds: 5
-            periodSeconds: 10
-          volumeMounts:
-            - name: theme
-              mountPath: /app/sunbeam-theme.css
-              subPath: sunbeam-theme.css
-              readOnly: true
-          resources:
-            limits:
-              memory: 256Mi
-              cpu: 250m
-            requests:
-              memory: 64Mi
-              cpu: 50m
-      volumes:
-        - name: theme
-          configMap:
-            name: messages-frontend-theme