fix: ensure git remote origin is set when backup repo already exists

When the repo directory already existed from a previous init (e.g.
local-only init without remote), the origin remote was missing. Now
initRepo() verifies and sets/updates the remote on every startup.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/mcpd/src/services/backup/git-backup.service.ts

@@ -394,6 +394,18 @@ export class GitBackupService {
   private async initRepo(): Promise<void> {
     try {
       await access(join(REPO_DIR, '.git'));
+      // Repo exists — ensure remote origin is correct
+      try {
+        const { stdout: currentUrl } = await execFile('git', ['remote', 'get-url', 'origin'], { cwd: REPO_DIR });
+        if (currentUrl.trim() !== this.repoUrl) {
+          await execFile('git', ['remote', 'set-url', 'origin', this.repoUrl!], { cwd: REPO_DIR });
+          console.log(`[git-backup] Updated remote origin to ${this.repoUrl}`);
+        }
+      } catch {
+        // No remote — add it
+        await execFile('git', ['remote', 'add', 'origin', this.repoUrl!], { cwd: REPO_DIR });
+        console.log(`[git-backup] Added remote origin: ${this.repoUrl}`);
+      }
       console.log('[git-backup] Repo already cloned');
       return;
     } catch {