ui(deploy): remove Exposed Ports field from Resources tab

The field was cosmetic — `containerConfig.exposedPorts` only fed Docker's
`Config.ExposedPorts` metadata via `withExposedPorts(...)`. It never
published a host port and Traefik routing uses `appPort` from the label
builder, not this list. Users reading the label "Exposed Ports" reasonably
expected it to expose their port externally; removing it until real
multi-port Traefik routing lands (tracked in #149).

Backend DTOs (`ContainerRequest.exposedPorts`, `ConfigMerger.intList
("exposedPorts")`) are left in place so existing containerConfig JSONB
rows continue to deserialize. New writes from the UI will no longer
include the field.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

ui/src/pages/AppsTab/AppDeploymentPage/ConfigTabs/readOnly-contract.test.tsx

@@ -47,7 +47,6 @@ const defaultResources: ResourcesFormState = {
   memoryReserve: '',
   cpuRequest: '500',
   cpuLimit: '',
-  ports: [],
   appPort: '8080',
   replicas: '1',
   deployStrategy: 'blue-green',