Refa: Move HTTP API tests to top-level test directory (#8042)

### What problem does this PR solve?

Move test cases only - CI still runs tests under sdk/python

### Type of change

- [x] Refactoring

test/utils/__init__.py

@@ -0,0 +1,63 @@
+#
+#  Copyright 2025 The InfiniFlow Authors. All Rights Reserved.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+#
+
+import base64
+import functools
+import hashlib
+import time
+from pathlib import Path
+
+
+def encode_avatar(image_path):
+    with Path.open(image_path, "rb") as file:
+        binary_data = file.read()
+    base64_encoded = base64.b64encode(binary_data).decode("utf-8")
+    return base64_encoded
+
+
+def compare_by_hash(file1, file2, algorithm="sha256"):
+    def _calc_hash(file_path):
+        hash_func = hashlib.new(algorithm)
+        with open(file_path, "rb") as f:
+            while chunk := f.read(8192):
+                hash_func.update(chunk)
+        return hash_func.hexdigest()
+
+    return _calc_hash(file1) == _calc_hash(file2)
+
+
+def wait_for(timeout=10, interval=1, error_msg="Timeout"):
+    def decorator(func):
+        @functools.wraps(func)
+        def wrapper(*args, **kwargs):
+            start_time = time.time()
+            while True:
+                result = func(*args, **kwargs)
+                if result is True:
+                    return result
+                elapsed = time.time() - start_time
+                if elapsed > timeout:
+                    assert False, error_msg
+                time.sleep(interval)
+
+        return wrapper
+
+    return decorator
+
+
+def is_sorted(data, field, descending=True):
+    timestamps = [ds[field] for ds in data]
+    return all(a >= b for a, b in zip(timestamps, timestamps[1:])) if descending else all(a <= b for a, b in zip(timestamps, timestamps[1:]))