fix(amp): remove unsupported --permission-mode CLI flags

[tamish560]

What

Removes appendPermissionFlags from the Amp adapter. Amp does not support --permission-mode CLI flags - its permission model is configured through settings/plugins (amp.permissions, amp.guardedFiles.allowlist, amp.dangerouslyAllowAll), not CLI arguments.

Why

When AO launches Amp with a non-default permission mode, it builds commands like amp --permission-mode acceptEdits which can fail on startup or exit before opening the TUI. Projects that configure worker permissions globally make Amp workers fail to start even though plain amp works fine.

Closes #2561

Changes

• Removed appendPermissionFlags function from amp.go
• Removed the call to appendPermissionFlags in GetLaunchCommand
• Removed the call to appendPermissionFlags in GetRestoreCommand
• Updated comment on GetLaunchCommand to reflect amp (no flags)
• Updated tests: all permission modes now produce just {"amp"} with no --permission-mode flags
• Updated restore command test to expect {"amp", "--resume", "T-abc123"} without permission flags

Testing

All existing tests pass with the updated expectations. The test table in TestGetLaunchCommandMapsPermissionModes now verifies that every permission mode (default, acceptEdits, auto, bypass) omits --permission-mode from the command.

[tamish560]

Closing this as #2573 by @VenkataSakethDakuri was already merged on July 10. Should have checked existing PRs before opening this one.