[Feature]: Add Go to Line command #75
Description
Problem
Fast navigation to a specific line is still missing from the editor workflow.
Proposed solution
Add a native Go to Line command with keyboard shortcut support and a lightweight input surface that jumps the current editor to the requested line.
Acceptance criteria
- Users can open Go to Line from a command or shortcut
- The current editor jumps to the requested line
- Invalid line numbers are handled safely
- macOS and iPad keyboard workflows are supported
- Accessibility labels and focus handoff stay correct