Disable example caching for instant startup

Pre-caching 12 scenes takes 30+ minutes. Disabled for faster startup.

app.py

@@ -66,16 +66,9 @@ if __name__ == "__main__":
     examples_dir = os.path.join(workspace_dir, "examples")
     examples_exist = os.path.exists(examples_dir)
     
-    # Check if caching is enabled via environment variable (default: True if examples exist)
-    # Allow disabling via environment variable: DA3_CACHE_EXAMPLES=false
-    cache_examples_env = os.environ.get("DA3_CACHE_EXAMPLES", "").lower()
-    if cache_examples_env in ("false", "0", "no"):
-        cache_examples = False
-    elif cache_examples_env in ("true", "1", "yes"):
-        cache_examples = True
-    else:
-        # Default: enable caching if examples directory exists
-        cache_examples = examples_exist
+    # Disable example caching for faster startup
+    # The original demo pre-caches 12 scenes which takes 30+ minutes
+    cache_examples = False
     
     # Get cache_gs_tag from environment variable (default: "dl3dv")
     cache_gs_tag = os.environ.get("DA3_CACHE_GS_TAG", "dl3dv")