feat: manually mirror opencoze's code from bytedance

Change-Id: I09a73aadda978ad9511264a756b2ce51f5761adf

frontend/packages/common/chat-area/chat-area-plugin-reasoning/src/custom-components/message-inner-addon-bottom/index.tsx

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2025 coze-dev Authors
+ *
+ * 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 { memo, useEffect, useRef, useState, type FC } from 'react';
+
+import { type Message, type ContentType } from '@coze-common/chat-core';
+import { MdBoxLazy } from '@coze-arch/bot-md-box-adapter/lazy';
+
+type IProps = Record<'message', Message<ContentType>>;
+
+// export const BizMessageInnerAddonBottom: FC<IProps> = p =>
+//   p.message.role === 'assistant' && p.message.reasoning_content ? (
+//     <div className="my-[8px] px-[14px] border-solid border-[0] border-l-[0.25em] border-l-[var(--color-border-default)] text-[var(--color-fg-muted)]">
+//       {p.message.reasoning_content}
+//     </div>
+//   ) : null;
+
+export const BizMessageInnerAddonBottom: FC<IProps> = memo(
+  p => {
+    const [reasoningFinished, setReasoningFinished] = useState(false);
+    const ref = useRef(p.message.reasoning_content);
+
+    useEffect(() => {
+      setReasoningFinished(ref.current === p.message.reasoning_content);
+
+      return () => {
+        ref.current = p.message.reasoning_content;
+      };
+      // content 用来触发 reasoning 的 rerender
+    }, [p.message.reasoning_content, p.message.content]);
+
+    return p.message.role === 'assistant' && p.message.reasoning_content ? (
+      <div className="my-[8px]">
+        <MdBoxLazy
+          markDown={`${p.message.reasoning_content.replace(/^/gm, '> ')}`}
+          showIndicator={!p.message.is_finish && !reasoningFinished}
+        ></MdBoxLazy>
+      </div>
+    ) : null;
+  },
+  (prev, next) =>
+    prev.message.role === next.message.role &&
+    prev.message.is_finish === next.message.is_finish &&
+    prev.message.reasoning_content === next.message.reasoning_content &&
+    prev.message.content === next.message.content,
+);