feat: Enable workflow control operations by default

[xerial]

Summary

Enable kill_attempt, retry_session, and retry_attempt operations by default without requiring TD_ENABLE_UPDATES.

Changes

Removed TD_ENABLE_UPDATES requirement from:

• kill_attempt - Sends a cancellation request to a running attempt
• retry_session - Creates a new attempt for a session
• retry_attempt - Creates a new attempt with resume capabilities

Rationale

These operations are safe and don't directly modify or delete data:

• Retry operations create new attempts rather than modifying existing ones
• Kill operation sends a cancellation request, doesn't forcefully terminate
• The workflow API itself handles validation and ensures operations are safe

Updated

• Removed enable_updates checks from the three workflow control tools
• Updated tests to reflect that these operations work without TD_ENABLE_UPDATES
• Updated design documentation to clarify security considerations

Testing

• All existing tests pass
• Updated tests verify that operations work regardless of enable_updates setting
• Integration tests confirm the operations are available by default

🤖 Generated with Claude Code