fix: set CAMELEER_DB_SCHEMA=public for existing main deployment

Existing deployment has tables in public schema. The new tenant_default
default breaks startup because Flyway sees an empty schema. Override to
public for backward compat; new deployments use the tenant-derived default.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

deploy/overlays/main/kustomization.yaml

@@ -40,6 +40,8 @@ patches:
                 env:
                   - name: CAMELEER_UI_ORIGIN
                     value: "http://192.168.50.86:30090"
+                  - name: CAMELEER_DB_SCHEMA
+                    value: "public"
   # UI ConfigMap: production API URL
   - target:
       kind: ConfigMap