checkpoint: stalwart deploy, beam-design, migration scripts, config tweaks

Stalwart + Bulwark mail server deployment with OIDC, TLS cert, vault
secrets. Beam design service. Pingora config cleanup. SeaweedFS
replication fix. Kratos values tweak. Migration scripts for mbox/messages
/calendars from La Suite to Stalwart.

base/stalwart/bulwark-service.yaml

@@ -0,0 +1,12 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: bulwark
+  namespace: stalwart
+spec:
+  selector:
+    app: bulwark
+  ports:
+    - name: http
+      port: 80
+      targetPort: 3000