fix bug of image path traversal

app.py

@@ -66,11 +66,11 @@ for key, (path, dur, mel) in create_sound_library.items():
     if not os.path.exists(path):
         generate_chimes_wav(path, duration=dur, melody_type=mel)
 
-COVERS_DIR = Path("assets/covers")
+COVERS_DIR = Path(__file__).parent / "assets" / "covers"
 
 def cover_path(slug: str) -> str:
     p = COVERS_DIR / f"{slug}.png"
-    return f"/gradio_api/file={p.as_posix()}"
+    return f"/gradio_api/file={p.resolve().as_posix()}"
 
 def load_books_from_stories(stories_dir="stories"):
     books = []
@@ -457,7 +457,7 @@ with gr.Blocks(css=css_code, title="VoiceBook Gradio Hub") as demo:
 
                     # Story text display + slider
                     story_text_display = gr.HTML(visible=False)
-                    timeline_slider = gr.Slider(minimum=0, maximum=0, step=1, value=0, label="📍 Story position (paragraph)", visible=False)
+                    timeline_slider = gr.Slider(minimum=0, maximum=100, step=1, value=0, label="📍 Story position (paragraph)", visible=False)
 
                     # Q&A Panel
                     qa_panel = gr.HTML("""
@@ -922,4 +922,4 @@ with gr.Blocks(css=css_code, title="VoiceBook Gradio Hub") as demo:
     offline_toggle.change(toggle_outage_sandbox, inputs=[offline_toggle], outputs=[system_error_modal, main_tabs])
 
 if __name__ == "__main__":
-    demo.queue().launch(allowed_paths=["assets"])
+    demo.queue().launch(allowed_paths=[str(Path(__file__).parent / "assets")])