fix(electrobun): wizard 7 fixes — validation, GitLab, SSHFS, icons, model dropdown, keyboard nav

- Git Platform: validates repo via git.probe before enabling Next, supports GitHub + GitLab + any git URL
- Template dir configurable in Advanced Settings (template_dir key)
- SSHFS: checks sshfs availability, mountpoint selector when enabled
- CustomDropdown: flip-up when insufficient space below
- 50 Lucide icons (was 24) with categories (AI, Data, DevOps, Security, Media, Comms)
- Model: CustomDropdown from live API, max_tokens as slider, effort only with adaptive thinking
- Keyboard: Escape closes wizard, Tab navigation with :focus-visible rings, source cards navigable

ui-electrobun/src/shared/pty-rpc-schema.ts

@@ -242,11 +242,17 @@ export type PtyRPCRequests = {
     response: { ok: boolean; branches: string[]; defaultBranch: string; error?: string };
   };
 
+  /** Check if sshfs is installed. */
+  "ssh.checkSshfs": {
+    params: Record<string, never>;
+    response: { installed: boolean; path: string | null };
+  };
+
   // ── Project templates RPC ───────────────────────────────────────────────────
 
-  /** Return available project templates. */
+  /** Return available project templates. Optionally pass custom template dir. */
   "project.templates": {
-    params: Record<string, never>;
+    params: { templateDir?: string };
     response: {
       templates: Array<{
         id: string;