fix: v2.6.1 — panes start in their folder again after an update (#69), Changes panel stacks every repo, clickable paths in chat

- #69: tmux applies a pane's `-c` only while its server's own cwd exists.
  The server was forked from the dashboard's cwd (the plugin cache dir),
  outlives updates, and the old cache dir is pruned — after that every new
  pane started in a deleted directory, where `claude` died at once ("run not
  found") and a shell printed getcwd errors. tmux calls now run from `/`,
  and the pane's sh wrapper cds into its folder itself, which also heals a
  tmux server that is already stuck.
- Changes panel: a workspace's extra folders are sections stacked under the
  workspace folder (VS Code Source Control style), with Close repository /
  Close other repositories on a header's right-click.
- Chat: URLs and absolute paths are links; Claude Code's `[Image: source:]`
  line folds into its turn; uploads under `<data dir>/drops/` are listed.
- Update check: a checkout holding commits a newer release lacks reports
  `diverged_from_release` instead of offering a fast-forward that can only fail.

server/lib/tmux.js

@@ -38,7 +38,9 @@ const { execFile, execFileSync } = require("node:child_process");
 // try/catch and treats failure as "no session" — piping tmux's own
 // "error connecting to ..." noise to the process's stderr just spams the
 // journal on every poll while no tmux server is running yet.
-const EXEC_OPTS = { encoding: "utf8", stdio: ["pipe", "pipe", "ignore"] };
+// cwd "/": a tmux server is forked from the call that starts it and keeps
+// that cwd; once it is deleted, tmux ignores every pane's `-c` (issue #69).
+const EXEC_OPTS = { encoding: "utf8", stdio: ["pipe", "pipe", "ignore"], cwd: "/" };
 let execImpl = (args, opts = EXEC_OPTS) => execFileSync("tmux", args, opts);
 
 // Linux: the tmux server lives in the cgroup of whatever started it — the