feat: Add MinIO endpoint/public URL configuration via settings UI

Store endpointUrl and publicUrl in cloudinary_config DB table so
MinIO connection can be fully configured from the app settings
without needing environment variables.

- DB migration: adds endpoint_url and public_url columns
- Schema: adds endpointUrl/publicUrl to cloudinaryConfig table
- MinIO service: reads endpoint from DB (falls back to MINIO_ENDPOINT env)
- buildMinioUrl: accepts optional publicUrl override from DB config
- All routes updated to pass config.publicUrl to buildMinioUrl
- Settings UI (desktop + mobile): adds Endpoint URL and Public URL fields

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

shared/schema.ts

@@ -117,6 +117,8 @@ export const cloudinaryConfig = pgTable("cloudinary_config", {
   apiKey: text("api_key").notNull(),
   apiSecret: text("api_secret").notNull(),
   logoPublicId: text("logo_public_id"),
+  endpointUrl: text("endpoint_url"),
+  publicUrl: text("public_url"),
   createdAt: timestamp("created_at").defaultNow(),
   updatedAt: timestamp("updated_at").defaultNow(),
 });