feat(ui): dynamically load playlists and artists in library

src/lib/library/scanner.ts

@@ -0,0 +1,72 @@
+import { readDir } from '@tauri-apps/plugin-fs';
+
+export interface Artist {
+  name: string;
+  path: string;
+}
+
+export interface Playlist {
+  name: string;
+  path: string;
+}
+
+/**
+ * Scan music folder for artists (each folder is an artist)
+ */
+export async function scanArtists(musicFolderPath: string): Promise<Artist[]> {
+  try {
+    const entries = await readDir(musicFolderPath);
+
+    const artists: Artist[] = [];
+
+    for (const entry of entries) {
+      if (entry.isDirectory) {
+        artists.push({
+          name: entry.name,
+          path: `${musicFolderPath}/${entry.name}`
+        });
+      }
+    }
+
+    // Sort alphabetically
+    artists.sort((a, b) => a.name.localeCompare(b.name));
+
+    return artists;
+  } catch (error) {
+    console.error('Error scanning artists:', error);
+    return [];
+  }
+}
+
+/**
+ * Scan playlists folder for m3u/m3u8 files
+ */
+export async function scanPlaylists(playlistsFolderPath: string): Promise<Playlist[]> {
+  try {
+    const entries = await readDir(playlistsFolderPath);
+
+    const playlists: Playlist[] = [];
+
+    for (const entry of entries) {
+      if (!entry.isDirectory) {
+        const isPlaylist = entry.name.endsWith('.m3u') || entry.name.endsWith('.m3u8');
+        if (isPlaylist) {
+          // Remove extension for display name
+          const nameWithoutExt = entry.name.replace(/\.(m3u8?|M3U8?)$/, '');
+          playlists.push({
+            name: nameWithoutExt,
+            path: `${playlistsFolderPath}/${entry.name}`
+          });
+        }
+      }
+    }
+
+    // Sort alphabetically
+    playlists.sort((a, b) => a.name.localeCompare(b.name));
+
+    return playlists;
+  } catch (error) {
+    console.error('Error scanning playlists:', error);
+    return [];
+  }
+}