Remove vestigial duplicate checking

app/packet_processor.py

@@ -86,19 +86,14 @@ async def create_message_from_decrypted(
     )
 
     if msg_id is None:
-        # Duplicate detected - find existing message ID for packet linkage
-        existing_id = await MessageRepository.find_duplicate(
-            conversation_key=channel_key_normalized,
-            text=text,
-            sender_timestamp=timestamp,
-        )
-        logger.debug(
-            "Duplicate message detected for channel %s (existing id=%s)",
+        # This shouldn't happen - raw packets are deduplicated by payload hash,
+        # so the same message content shouldn't be created twice. Log a warning.
+        logger.warning(
+            "Unexpected duplicate message for channel %s (packet_id=%d) - "
+            "this may indicate a bug in payload deduplication",
             channel_key_normalized[:8],
-            existing_id,
+            packet_id,
         )
-        if existing_id:
-            await RawPacketRepository.mark_decrypted(packet_id, existing_id)
         return None
 
     logger.info("Stored channel message %d for channel %s", msg_id, channel_key_normalized[:8])

app/repository.py

@@ -377,33 +377,6 @@ class MessageRepository:
         row = await cursor.fetchone()
         return row["acked"] if row else 1
 
-    @staticmethod
-    async def find_duplicate(
-        conversation_key: str,
-        text: str,
-        sender_timestamp: int | None,
-    ) -> int | None:
-        """Find existing message with same content (for deduplication).
-
-        Returns message ID if found, None otherwise.
-        Used to detect the same message arriving via multiple RF paths.
-        """
-        if sender_timestamp is None:
-            return None
-
-        cursor = await db.conn.execute(
-            """
-            SELECT id FROM messages
-            WHERE conversation_key = ?
-              AND text = ?
-              AND sender_timestamp = ?
-            LIMIT 1
-            """,
-            (conversation_key, text, sender_timestamp),
-        )
-        row = await cursor.fetchone()
-        return row["id"] if row else None
-
     @staticmethod
     async def get_bulk(
         conversations: list[dict],