Components.AI: Add built-in copy, retry, and edit-and-resubmit actions

### Is your feature request related to a problem? Please describe the problem.

Common answer and request actions are missing, and the engine cannot truncate/replace conversation history for retry or edit-and-resubmit.

### Describe the solution you'd like

Add copy-message and retry/regenerate actions plus edit-and-resubmit for user messages. Editing must use explicit lifecycle APIs to replace/truncate affected turns, preserve consistency, and surface errors rather than mutating history silently.

### Additional context

Leaf task for #68227 requirements F5-F6. Depends on action menus, clipboard interop, and lifecycle APIs.

Start with the requirements in #68227, especially F5-F6, then review the action menus, clipboard interop, and lifecycle APIs named in this issue. Done means built-in copy, retry/regenerate, and edit-and-resubmit actions that use explicit lifecycle APIs, preserve conversation consistency, and surface errors.

Written by the indexing model from the issue text.