feat(clone): add repository cloning flow to UI and backend

This introduces a new Tauri command to clone a remote repository into a
validated destination folder, then return the full repository bundle for
immediate rendering. The Svelte app gains a clone dialog and a new action
in repository management, wiring the cloned bundle into existing refresh
helpers. Dialog backdrops were also adjusted to rely on explicit close
controls.

- Add clone_repository command and core cloning logic in Rust
- Create CloneRepositoryDialog and integrate it into App.svelte
- Improve clone-related styling and tighten dialog backdrop behavior

src/lib/git.ts

@@ -34,6 +34,20 @@ export function openRepositoryBundle(path: string, commitLimit = 100): Promise<R
   return invoke<RepositoryBundle>("open_repository_bundle", { path, commitLimit });
 }
 
+export function cloneRepository(
+  remoteUrl: string,
+  parentPath: string,
+  directoryName?: string,
+  commitLimit = 100,
+): Promise<RepositoryBundle> {
+  return invoke<RepositoryBundle>("clone_repository", {
+    remoteUrl,
+    parentPath,
+    directoryName: directoryName?.trim() ? directoryName.trim() : null,
+    commitLimit,
+  });
+}
+
 export function getStatus(path: string): Promise<GitStatus> {
   return invoke<GitStatus>("get_status", { path });
 }