* Fix claude-teams pane anchoring: main-vertical layout + focus
Claude's agent teams sends `split-window -h` for each teammate then
`select-layout main-vertical` to stack them vertically. Three fixes:
1. Implement select-layout main-vertical: track layout state in the
tmux compat store so subsequent horizontal splits of the leader
pane get redirected to vertical splits of the right-side column.
2. Pass focus:false to surface.split from the split-window handler
so internal bonsplit focus stays on the leader pane.
3. Fix tmuxCompatStoreURL to respect $HOME env var (was using
NSString.expandingTildeInPath which ignores $HOME).
Closes https://github.com/manaflow-ai/cmux/issues/2118
* Fix claude-teams split routing: auto-seed main-vertical on first right split
The split-window routing was broken in two ways:
1. After the first teammate split (right), the main-vertical state wasn't
being created, so all subsequent splits also went right instead of
stacking down in the right column.
2. The old code only redirected splits when main-vertical was already active
AND the target was the leader surface. Claude's teams protocol targets
arbitrary panes from list-panes, not necessarily the leader.
Now the first teammate split goes right (creating the column), auto-seeds
the main-vertical state, and all subsequent splits stack downward. The
caller's surface (CMUX_SURFACE_ID) is used as the anchor regardless of
which pane Claude targets.
Also adds caller surface preference in pane target resolution so the
caller's exact surface is used when the target pane matches, preventing
stale selected-surface references after tab switches.
---------
Co-authored-by: Lawrence Chen <lawrencecchen@users.noreply.github.com>
