Add @spaces.GPU so ZeroGPU startup detection passes

app.py

@@ -3,6 +3,11 @@ from pathlib import Path
 
 sys.path.insert(0, str(Path(__file__).resolve().parent))
 
+try:
+    import spaces
+except ImportError:
+    spaces = None
+
 from jinja2 import Environment
 import gradio as gr
 
@@ -18,6 +23,12 @@ from llm_query.utils import (
 )
 
 
+def zero_gpu(duration: int = 120):
+    if spaces is None:
+        return lambda function: function
+    return spaces.GPU(duration=duration)
+
+
 MODEL_NAME = "gpt-5.6-terra"
 AUX_SYNC_CONFIG_NAME = "config.v0.6.json"
 SPAN_MARKING_CONFIG_NAME = "config.span_marking.v0.6.json"
@@ -82,6 +93,7 @@ def empty_tooltips(tokens: tuple[str, ...]) -> tuple[str, ...]:
     return tuple("" for _ in tokens)
 
 
+@zero_gpu(duration=120)
 def generate_diff(text_a: str, text_b: str):
     aux_client = get_aux_sync_client()
     marking_client = get_span_marking_client()