Refactor portal module discovery flow

[heswell]

Summary

• consume module registry metadata from the portal websocket LOGIN_SUCCESS response
• route module admin through the portal connection and user admin through its standalone VUU server
• remove the browser REST/static module-registry flow and update the table browser and architecture documentation
• preserve the public ConnectionManager.connect status-return contract while exposing the login payload internally

Validation

• targeted Vitest suite: 72 tests passed
• websocket worker build
• module federation application build