Add anonymous listening support and redesign web-player UI

Backend:
- Expose GET /config/playback so the frontend can detect whether
  anonymous listening is enabled without requiring auth
- Wire anonymous access through track streaming and YouTube resolve flows

Frontend:
- Allow browsing/listening without a session when the backend enables it
- Redesign Inicio, Sidebar and top bar with a new dark theme, typography,
  and layout (top bar with live quick-search, sticky/blurred on scroll)
- Populate Top música, Popular and Recomendados with real Musify +
  YouTube Music data instead of placeholders
- Various shape, spacing, color and animation refinements across the
  redesigned components

web-player/src/lib/api/schema.d.ts

@@ -177,6 +177,23 @@ export interface paths {
         patch?: never;
         trace?: never;
     };
+    "/config/playback": {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        /** Get The Public Playback Configuration (Whether Anonymous Listening Is Allowed). Works Anonymously. */
+        get: operations["GetPlaybackPublicConfig"];
+        put?: never;
+        post?: never;
+        delete?: never;
+        options?: never;
+        head?: never;
+        patch?: never;
+        trace?: never;
+    };
     "/mixes": {
         parameters: {
             query?: never;
@@ -742,6 +759,11 @@ export interface components {
             hasNextPage: boolean;
             hasPreviousPage: boolean;
         };
+        PlaybackPublicConfigResponse: {
+            allowAnonymousListening: boolean;
+            /** Format: int32 */
+            anonymousFragmentSeconds: number | string;
+        };
         PlayListApplicationResponse: {
             /** Format: uuid */
             id: string;
@@ -1423,6 +1445,26 @@ export interface operations {
             };
         };
     };
+    GetPlaybackPublicConfig: {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        requestBody?: never;
+        responses: {
+            /** @description OK */
+            200: {
+                headers: {
+                    [name: string]: unknown;
+                };
+                content: {
+                    "application/json": components["schemas"]["PlaybackPublicConfigResponse"];
+                };
+            };
+        };
+    };
     GetMixes: {
         parameters: {
             query?: never;