v0.52.0: Session sharing, ctrl+z suspend, and bug fixes

New features

- /share command - Share your current session with organization members, copies share URL to clipboard

Improvements

- Ctrl+Z suspend - Handle ctrl+z suspend like other TUIs
- Decoupled modes and autonomy - Modes and autonomy levels are now independent settings in the TUI

Bug fixes

- Task tool view - Fixed Ctrl+O view for Task tool
- Settings file writes - Avoid unnecessary file writes when updating unrelated settings
- Unified tool display - Fixed tool result pending display issue
- Subagent version - Fixed subagent spawning to use correct droid version