Implements Tasks 8 and 9 of F2-A+B: async agent creation from entity UUID
and async per-agent profile regeneration, both with atomic profile file writes.
Refactors generate_profile_from_entity to accept extra_instructions instead
of requiring user_id (renamed internal logic to _generate_single_profile).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Implements atomic agent profile editing with manually_edited flag.
Blocks edits when simulation is running or completed.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>