Improve git worktree session workflow

project.sh

@@ -57,7 +57,21 @@ if [[ "${1:-}" == --pick ]]; then
   ) || exit 0
   [ -n "$project" ] || exit 0
 
-  tmux new-window -n "$project" -c "$projects_dir/$project"
+  # Inside a session for this same project, e.g. one created by `session -p`,
+  # the slug only repeats the session name, so name the window after the branch
+  # checked out there instead — a worktree's whole identity. Everything up to
+  # the `@` is the clone the worktrees hang off, and tmux rewrote `.` and `:` in
+  # the session name, so match both before comparing.
+  window_name=$project
+  session=$(tmux display -p '#S')
+  root=${project%%@*}
+  if [ "${root//[.:]/_}" = "$session" ]; then
+    branch=$(git -C "$projects_dir/$project" symbolic-ref --short HEAD 2>/dev/null ||
+      git -C "$projects_dir/$project" rev-parse --short HEAD 2>/dev/null || true)
+    window_name=${branch:-$project}
+  fi
+
+  tmux new-window -n "$window_name" -c "$projects_dir/$project"
   ~/.local/share/tmux/layouts/window-auto
   exit
 fi