feat(drive): add drive picker in sidebar

- select by default the home drive

frontend/src/lib/api/endpoints/drives.ts

@@ -0,0 +1,15 @@
+/**
+ * Drives endpoints. D0 ships read-only listing; mutations (create / rename /
+ * member changes) land in D2/D3 and will be added here under the same shape.
+ *
+ * Consumers usually go through the `drives` store (`$lib/stores/drives.svelte`)
+ * which dedupes the request and caches the list — touch this module directly
+ * only when bypassing the cache is intentional (e.g. an explicit refresh).
+ */
+import { apiJson } from '$lib/api/client';
+import type { Drive } from '$lib/api/types';
+
+/** `GET /api/drives` — every drive the caller can read, default first by convention. */
+export function listDrives(): Promise<Drive[]> {
+	return apiJson<Drive[]>('/api/drives', { credentials: 'same-origin' });
+}

frontend/src/lib/api/endpoints/folders.ts

@@ -103,11 +103,6 @@ function parseListing(raw: unknown): FolderListing {
 	};
 }
 
-/** Top-level folders for the user; the first entry is the home folder. */
-export function listRootFolders(): Promise<FolderItem[]> {
-	return apiJson<FolderItem[]>('/api/folders', { credentials: 'same-origin' });
-}
-
 export async function getFolder(id: string): Promise<FolderItem> {
 	const folder = await apiJson<FolderItem>(`/api/folders/${id}`, NO_CACHE);
 	rememberFolderName(folder.id, folder.name);