feat: v2.7.8 — Artifacts hub, clone related repos as extra folders, quieter resume prompt

- Artifacts (/artifacts): claude.ai pages sessions publish (captured from the
  Artifact tool's hook), pinned workspace files, skills and plugins, each
  kept as a snapshot; shared ones appear in a Hub and a skill or plugin
  installs into the viewer's own account (server/lib/artifacts.js,
  /api/artifacts, docs/plans/artifacts/).
- Workspace extra folders: clone one or more related repos beside the
  workspace and add them in one step (POST /api/lanes/:id/sources/clone).
- A pane that ended by itself while tmux kept running is no longer offered
  for resume (tmux.serverStartedAt in reconcileOrphans).
- Changes panel: a folder that is not a git repo opens on Files, and its
  files open from there.
- Plus the parallel sessions' work in this tree: File Explorer button in the
  panel header, user delete, RSA SSH keys, chat/terminal and pet fixes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/routes/git-identity.js

@@ -26,6 +26,7 @@ const STATUS = {
   EHOSTIDENTITY: 403,
   EBADAUTHOR: 400,
   ESTOREUNREADABLE: 409,
+  EBADKEYTYPE: 400,
 };
 
 function fail(res, e) {
@@ -66,8 +67,9 @@ router.get("/", async (req, res) => {
 router.post("/ssh-key", sameOriginGuard, async (req, res) => {
   try {
     const account = accountOf(req, { write: true });
-    identity.generateSshKey(account, {
+    await identity.generateSshKey(account, {
       replace: req.body?.replace === true,
+      type: req.body?.type === "rsa" ? "rsa" : "ed25519",
       comment: req.user?.username ? `${req.user.username}@agenthub` : "agenthub",
     });
     res.status(201).json(await view(account));