fix(feishu): split card messages when content has multiple tables

Feishu rejects interactive cards that contain more than one table element
(API error 11310: card table number over limit).

Add FeishuChannel._split_elements_by_table_limit() which partitions the flat
card-elements list into groups of at most one table each.  The send() method
now iterates over these groups and sends each as its own card message, so all
tables are delivered to the user instead of the entire message being dropped.

Single-table and table-free messages are unaffected (one card, same as before).

Fixes #1382

nanobot/channels/feishu.py

@@ -413,6 +413,34 @@ class FeishuChannel(BaseChannel):
             elements.extend(self._split_headings(remaining))
         return elements or [{"tag": "markdown", "content": content}]
 
+    @staticmethod
+    def _split_elements_by_table_limit(elements: list[dict], max_tables: int = 1) -> list[list[dict]]:
+        """Split card elements into groups with at most *max_tables* table elements each.
+
+        Feishu cards have a hard limit of one table per card (API error 11310).
+        When the rendered content contains multiple markdown tables each table is
+        placed in a separate card message so every table reaches the user.
+        """
+        if not elements:
+            return [[]]
+        groups: list[list[dict]] = []
+        current: list[dict] = []
+        table_count = 0
+        for el in elements:
+            if el.get("tag") == "table":
+                if table_count >= max_tables:
+                    if current:
+                        groups.append(current)
+                    current = []
+                    table_count = 0
+                current.append(el)
+                table_count += 1
+            else:
+                current.append(el)
+        if current:
+            groups.append(current)
+        return groups or [[]]
+
     def _split_headings(self, content: str) -> list[dict]:
         """Split content by headings, converting headings to div elements."""
         protected = content
@@ -653,11 +681,13 @@ class FeishuChannel(BaseChannel):
                         )
 
             if msg.content and msg.content.strip():
-                card = {"config": {"wide_screen_mode": True}, "elements": self._build_card_elements(msg.content)}
-                await loop.run_in_executor(
-                    None, self._send_message_sync,
-                    receive_id_type, msg.chat_id, "interactive", json.dumps(card, ensure_ascii=False),
-                )
+                elements = self._build_card_elements(msg.content)
+                for chunk in self._split_elements_by_table_limit(elements):
+                    card = {"config": {"wide_screen_mode": True}, "elements": chunk}
+                    await loop.run_in_executor(
+                        None, self._send_message_sync,
+                        receive_id_type, msg.chat_id, "interactive", json.dumps(card, ensure_ascii=False),
+                    )
 
         except Exception as e:
             logger.error("Error sending Feishu message: {}", e)