feat: add support for API usage with multimodal models (#4548)

* feat: add support for API usage with multimodal models

* completion_tokens contains num_image_tokens

* remove test_request.py

* fix: paddle.device.is_compiled_with_cuda()

* fix test_unstream_without_logprobs

fastdeploy/entrypoints/openai/usage_calculator.py

@@ -0,0 +1,33 @@
+"""
+# Copyright (c) 2025  PaddlePaddle 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 numpy as np
+
+
+def count_tokens(tokens):
+    """
+    Count the number of tokens in a nested list or array structure.
+    """
+    count = 0
+    stack = [tokens]
+    while stack:
+        current = stack.pop()
+        if isinstance(current, (list, tuple, np.ndarray)):
+            for item in reversed(current):
+                stack.append(item)
+        else:
+            count += 1
+    return count