feat: replace Unsplash cover URLs with local assets/covers/ PNG paths

- Add COVERS_DIR and cover_path() helper for Gradio file-serving URLs
- load_books_from_stories() uses cover_path(slug) per story filename
- player_title_info initial HTML uses cover_path() f-string instead of hardcoded Unsplash URL
- demo.queue().launch() adds allowed_paths=["assets"] for Gradio to serve local images

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app.py

@@ -4,6 +4,7 @@ import struct
 import wave
 import gradio as gr
 import time
+from pathlib import Path
 
 # Create directories for sample audio files
 os.makedirs("sample_sounds", exist_ok=True)
@@ -65,27 +66,22 @@ 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")
+
+def cover_path(slug: str) -> str:
+    """로컬 커버 이미지를 Gradio file-serving URL로 반환."""
+    p = COVERS_DIR / f"{slug}.png"
+    return f"/gradio_api/file={p.as_posix()}"
+
 def load_books_from_stories(stories_dir="stories"):
     books = []
     story_files = sorted(
         f for f in os.listdir(stories_dir) if f.endswith(".txt")
     ) if os.path.isdir(stories_dir) else []
 
-    cover_urls = [
-        "https://images.unsplash.com/photo-1544947950-fa07a98d237f?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1512820790803-83ca734da794?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1476275466078-4007374efbbe?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1456513080510-7bf3a84b82f8?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1492052722242-2554d0e99e3a?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1474932430478-367dbb6832c1?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1456513080510-7bf3a84b82f8?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1495640388908-05fa85288e61?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1476275466078-4007374efbbe?auto=format&fit=crop&q=80&w=400",
-        "https://images.unsplash.com/photo-1512820790803-83ca734da794?auto=format&fit=crop&q=80&w=400",
-    ]
-
     for i, filename in enumerate(story_files):
         title = filename.replace(".txt", "").replace("_", " ")
+        slug = filename.replace(".txt", "")
         # Read first non-empty line as synopsis opener
         synopsis = ""
         try:
@@ -99,7 +95,7 @@ def load_books_from_stories(stories_dir="stories"):
             "id": str(i + 1),
             "title": title,
             "author": "Public Domain",
-            "cover_url": cover_urls[i % len(cover_urls)],
+            "cover_url": cover_path(slug),
             "voice_name": "Mom’s Voice",
             "duration": 0,
             "elapsed_time": 0,
@@ -462,11 +458,11 @@ with gr.Blocks(css=css_code, title="VoiceBook Gradio Hub") as demo:
                     )
                     player_load_btn = gr.Button("Load Story", variant="secondary", size="sm")
 
-                    player_title_info = gr.HTML("""
+                    player_title_info = gr.HTML(f"""
                         <div style="text-align: center; margin-bottom: 24px; margin-top: 16px;">
-                            <img src="https://images.unsplash.com/photo-1544947950-fa07a98d237f?auto=format&fit=crop&q=80&w=400" style="width: 130px; height: 180px; object-fit: cover; border-radius: 12px; box-shadow: 0 4px 16px rgba(0,0,0,0.4); margin-bottom: 16px;" />
-                            <h3 style="font-family: 'Playfair Display', Georgia, serif; font-size: 22px; margin:0; color:#FAF7F2;">The Enchanted Willow</h3>
-                            <p style="font-size: 12px; color: #94a3b8; font-style: italic; margin-top:2px;">by Elena S. Thorne</p>
+                            <img src="{cover_path('The_Adventures_of_Puss_in_Boots')}" style="width: 130px; height: 180px; object-fit: cover; border-radius: 12px; box-shadow: 0 4px 16px rgba(0,0,0,0.4); margin-bottom: 16px;" />
+                            <h3 style="font-family: 'Playfair Display', Georgia, serif; font-size: 22px; margin:0; color:#FAF7F2;">Select a Story</h3>
+                            <p style="font-size: 12px; color: #94a3b8; font-style: italic; margin-top:2px;">Choose a story above and press Load</p>
                             <span style="display: inline-block; background: rgba(245, 132, 31, 0.15); color: #ffd3a6; font-size: 10.5px; font-weight: 700; padding: 3px 8px; border-radius: 999px; margin-top: 8px;">Active Narrator: Mom's Voice</span>
                         </div>
                     """)
@@ -1011,4 +1007,4 @@ with gr.Blocks(css=css_code, title="VoiceBook Gradio Hub") as demo:
 
 # Launch parameters configured for standard port and auto binding
 if __name__ == "__main__":
-    demo.queue().launch()
+    demo.queue().launch(allowed_paths=["assets"])