fix(platform): parse QQ official face messages to readable text (#6355)

Fixes #6294

QQ official bot receives emoji/sticker messages as raw XML-like tags:
`<faceType=4,faceId="",ext="eyJ0ZXh0IjoiW+a7oeWktOmXruWPt10ifQ==">`

This made the LLM unable to understand the emoji content.

Changes:
- Added `_parse_face_message()` method to parse face message format
- Decode base64 `ext` field to get emoji description text
- Replace face tags with `[表情:描述]` format for readability

Example:
- Input: `<faceType=4,faceId="",ext="eyJ0ZXh0IjoiW+a7oeWktOmXruWPt10ifQ==">`
- Output: `[表情:[满头问号]]`

Co-authored-by: ccsang <ccsang@users.noreply.github.com>

astrbot/core/platform/sources/qqofficial/qqofficial_platform_adapter.py

@@ -391,6 +391,47 @@ class QQOfficialPlatformAdapter(Platform):
                 else:
                     msg.append(File(name=filename, file=url, url=url))
 
+    @staticmethod
+    def _parse_face_message(content: str) -> str:
+        """Parse QQ official face message format and convert to readable text.
+
+        QQ official face message format:
+        <faceType=4,faceId="",ext="eyJ0ZXh0IjoiW+a7oeWktOmXruWPt10ifQ==">
+
+        The ext field contains base64-encoded JSON with a 'text' field
+        describing the emoji (e.g., '[满头问号]').
+
+        Args:
+            content: The message content that may contain face tags.
+
+        Returns:
+            Content with face tags replaced by readable emoji descriptions.
+        """
+        import base64
+        import json
+        import re
+
+        def replace_face(match):
+            face_tag = match.group(0)
+            # Extract ext field from the face tag
+            ext_match = re.search(r'ext="([^"]*)"', face_tag)
+            if ext_match:
+                try:
+                    ext_encoded = ext_match.group(1)
+                    # Decode base64 and parse JSON
+                    ext_decoded = base64.b64decode(ext_encoded).decode("utf-8")
+                    ext_data = json.loads(ext_decoded)
+                    emoji_text = ext_data.get("text", "")
+                    if emoji_text:
+                        return f"[表情:{emoji_text}]"
+                except Exception:
+                    pass
+            # Fallback if parsing fails
+            return "[表情]"
+
+        # Match face tags: <faceType=...>
+        return re.sub(r"<faceType=\d+[^>]*>", replace_face, content)
+
     @staticmethod
     def _parse_from_qqofficial(
         message: botpy.message.Message
@@ -416,7 +457,10 @@ class QQOfficialPlatformAdapter(Platform):
                 abm.group_id = message.group_openid
             else:
                 abm.sender = MessageMember(message.author.user_openid, "")
-            abm.message_str = message.content.strip()
+            # Parse face messages to readable text
+            abm.message_str = QQOfficialPlatformAdapter._parse_face_message(
+                message.content.strip()
+            )
             abm.self_id = "unknown_selfid"
             msg.append(At(qq="qq_official"))
             msg.append(Plain(abm.message_str))
@@ -432,10 +476,12 @@ class QQOfficialPlatformAdapter(Platform):
             else:
                 abm.self_id = ""
 
-            plain_content = message.content.replace(
-                "<@!" + str(abm.self_id) + ">",
-                "",
-            ).strip()
+            plain_content = QQOfficialPlatformAdapter._parse_face_message(
+                message.content.replace(
+                    "<@!" + str(abm.self_id) + ">",
+                    "",
+                ).strip()
+            )
 
             QQOfficialPlatformAdapter._append_attachments(msg, message.attachments)
             abm.message = msg