fix Space startup: lazy model load + module-level launch (no __main__ guard)

app.py

@@ -19,15 +19,23 @@ RES, N_PREFIX, MS = 224, 5, 4
 DEV = "cuda" if torch.cuda.is_available() else "cpu"
 TOKEN = os.environ.get("HF_TOKEN")
 
-model = AutoModel.from_pretrained(REPO, dtype=torch.float32, token=TOKEN,
-                                  attn_implementation="eager").eval().to(DEV)
 MEAN = torch.tensor([0.485, 0.456, 0.406]).view(3, 1, 1)
 STD = torch.tensor([0.229, 0.224, 0.225]).view(3, 1, 1)
 TREE_HTML = open("tree_widget.html").read()
 REVEAL_HTML = open("reveal_widget.html").read()
 
+_model = None
+def get_model():
+    """Lazy-load so the app binds its port immediately (avoids startup timeout)."""
+    global _model
+    if _model is None:
+        _model = AutoModel.from_pretrained(REPO, dtype=torch.float32, token=TOKEN,
+                                           attn_implementation="eager").eval().to(DEV)
+    return _model
+
 
 def build_tree(image):
+    model = get_model()
     img = image.convert("RGB").resize((RES, RES), Image.BICUBIC)
     arr = np.asarray(img).astype(np.float32) / 255
     x = ((torch.from_numpy(arr).permute(2, 0, 1) - MEAN) / STD).unsqueeze(0).to(DEV)
@@ -109,5 +117,4 @@ if gr is not None:
         btn.click(process, inp, [out_tree, out_rev])
         inp.upload(process, inp, [out_tree, out_rev])
 
-    if __name__ == "__main__":
-        demo.launch(server_name="0.0.0.0", server_port=int(os.environ.get("PORT", 7860)))
+    demo.queue().launch()   # module-level: HF Spaces imports this file, so no __main__ guard