feat: allow creating external repositories directly from git mount editor

- Add createExternalRepository API function
- Update GitMountEditor with "+ Add new repository..." option
- Show form to enter repo name and remote URL
- Auto-create external repo and refresh list on success
- Update config-profiles page to pass onCreateRepository handler

apps/web/src/api/git_repositories.ts

@@ -60,6 +60,13 @@ export async function createRepository(
   return response.data;
 }
 
+export async function createExternalRepository(
+  data: GitRepositoryCreate
+): Promise<GitRepository> {
+  const response = await apiClient.post<GitRepository>("/repositories", data);
+  return response.data;
+}
+
 export async function deleteRepository(projectId: string, repoId: string): Promise<void> {
   await apiClient.delete(`/projects/${projectId}/repositories/${repoId}`);
 }