chore: v2.8.13 — Artifacts reinstall/edit/installs, agent steps in chat, pick a local file to attach, Windows paths as links

- Chat: an Agent step shows its task, status and tool calls and opens its conversation in place; Windows paths (E:\…, C:/…) in replies open as files
- Prompt: attach a file on this computer by path (native picker), clearer too-large messages
- Artifacts: edit title/description and a skill's files (new snapshot), Reinstall, install history, Hub-only rows, skills installed into ~/.claude/skills and ~/.agents/skills
- Files: batch upload of small files in one extract
- AI Tools: npm install falls back to --prefix ~/.local when the global prefix is not writable

server/lib/run-as.js

@@ -301,6 +301,15 @@ function writeAsCanMove() {
   }
 }
 
+/** Whether the installed write-as knows `extract` (a batch upload; install-system re-run). */
+function writeAsCanExtract() {
+  try {
+    return /^\s*extract\)/m.test(fs.readFileSync(WRITE_AS, "utf8"));
+  } catch {
+    return false;
+  }
+}
+
 /**
  * Save `content` to `file` — as the member who owns the folder (S3), else
  * directly. In place, keeping the file's mode; `append` adds to the end.
@@ -634,6 +643,7 @@ module.exports = {
   writeAs,
   writeAsAsync,
   writeAsCanMove,
+  writeAsCanExtract,
   __setSpawnImpl,
   mkdirAs,
   makeMemberFolder,