fix: bare worktree regression after bump to gix v0.85

[jason5122]

Regressions

#192 introduced two regressions for bare worktrees:

1. Opening a worktree as a session now opens all worktrees as windows.
2. The session working dir is $GIT_DIR/worktrees/<name> instead of the path to the worktree.

Cause

gix 0.85 has two API changes:

1. Repository::kind() returns Kind::Common for bare worktrees instead of Kind::LinkedWorkTree.
2. is_bare() returns true despite the worktree having a checkout.

I'm pretty sure (1) is a gix bug. I made a PR to gix which should hopefully fix things! When that happens, we can revert the change to is_worktree(). Seems like (2) is an intentional API change.

Steps to Reproduce

mkdir -p /tmp/bug-demo && cd /tmp/bug-demo
git init --bare project
cd project
git worktree add master
git worktree add feature-a

cd ..
cat >config.toml <<EOF
list_worktrees = true

[[search_dirs]]
path = "/tmp/bug-demo"
depth = 1
EOF

TMS_CONFIG_FILE=/tmp/bug-demo/config.toml tms open-session 'project#master'
tmux list-windows -t 'project#master'
tmux display-message -t 'project#master' -p '#{session_path}'

Before

$ tmux list-windows -t 'project#master'
1: master- (1 panes) [181x50] [layout 2c0e,181x50,0,0,135] @134
2: feature-a* (1 panes) [181x50] [layout 2c0f,181x50,0,0,136] @135 (active)

$ tmux display-message -t 'project#master' -p '#{session_path}'
/private/tmp/bug-demo/project/worktrees/master

After

$ tmux list-windows -t 'project#master'
1: zsh* (1 panes) [181x50] [layout ac12,181x50,0,0,168] @166 (active)

$ tmux display-message -t 'project#master' -p '#{session_path}'
/private/tmp/bug-demo/project/master

[junglerobba]

can we add a comment here that this is (probably) a temp workaround that should be dropped eventually?

[junglerobba]

Thanks! Only applied some slight commit reorganization to keep the fixes in their own commits.