fix: add NumPy 2.0 compatibility for np.float_

- Handle AttributeError when np.float_ is not available in NumPy 2.0+
- Use try/except to gracefully fall back for newer NumPy versions

Author: luohf-infinilabs

easysearch/serializer.py

@@ -43,12 +43,14 @@
         np.uint32,
         np.uint64,
     )
-    FLOAT_TYPES += (
-        np.float_,
-        np.float16,
-        np.float32,
-        np.float64,
-    )
+    # np.float_ was removed in NumPy 2.0
+    float_types = [np.float16, np.float32, np.float64]
+    try:
+        float_types.insert(0, np.float_)
+    except AttributeError:
+        # NumPy 2.0+
+        pass
+    FLOAT_TYPES += tuple(float_types)
 except ImportError:
     np = None