## What changed
- With multi-backend support enabled, show the current host before the first submission and use `leader b` to cycle through available connections. Expose the shortcut as `tui.keymap.global.change_host`.
- Preserve the conversation name and composer draft, including cursor position, attachments, pending pastes, and literal versus shell-command interpretation of `!`.
- Save explicit host choices in user-only `tui.default_hosts`, scoped to the local project and user identity. Use the saved host for new conversations, falling back to the first available connection when it is unavailable.
- Prepare the destination and check directory trust before replacing the current conversation. Block switching during voice calls and active turns, and remove replaced blank conversations from the session overview.
## Testing
Add coverage for shortcut visibility and remapping, draft and name preservation, project/user preference isolation, unavailable-host fallback, destination trust and startup failures, and voice-call guards.
GitOrigin-RevId: def7b088951336bec8fe3962954fba9b861f91c6
Benjamin Carlsson
26f73fba8f