refactor: message storage format of webchat, support reply and file message segment (#3845)

* refactor: message storage format of webchat

* refactor: update image and record handling in webchat event processing

* fix: thinking placeholder in webchat

* feat: supports file upload in webchat

* feat: supports to delete attachments when webchat session is deleted

* perf: improve performance of file downloading

* refactor: remove unused import in chat route

* feat: add message timestamp formatting and localization support in chat

* fix: handle missing filename in file upload for chat route

* feat: enhance file handling in chat and webchat, supporting video uploads and improved attachment management

* fix: update property name for embedded files in message handling

* fix: compute variable errors after uninstalling plugins

* feat: supported for reply message and standarlize the message param

* fix: ensure message actions are displayed for the last message in the list

astrbot/core/db/sqlite.py

@@ -449,6 +449,18 @@ class SQLiteDatabase(BaseDatabase):
             result = await session.execute(query.offset(offset).limit(page_size))
             return result.scalars().all()
 
+    async def get_platform_message_history_by_id(
+        self, message_id: int
+    ) -> PlatformMessageHistory | None:
+        """Get a platform message history record by its ID."""
+        async with self.get_db() as session:
+            session: AsyncSession
+            query = select(PlatformMessageHistory).where(
+                PlatformMessageHistory.id == message_id
+            )
+            result = await session.execute(query)
+            return result.scalar_one_or_none()
+
     async def insert_attachment(self, path, type, mime_type):
         """Insert a new attachment record."""
         async with self.get_db() as session:
@@ -470,6 +482,48 @@ class SQLiteDatabase(BaseDatabase):
             result = await session.execute(query)
             return result.scalar_one_or_none()
 
+    async def get_attachments(self, attachment_ids: list[str]) -> list:
+        """Get multiple attachments by their IDs."""
+        if not attachment_ids:
+            return []
+        async with self.get_db() as session:
+            session: AsyncSession
+            query = select(Attachment).where(
+                Attachment.attachment_id.in_(attachment_ids)
+            )
+            result = await session.execute(query)
+            return list(result.scalars().all())
+
+    async def delete_attachment(self, attachment_id: str) -> bool:
+        """Delete an attachment by its ID.
+
+        Returns True if the attachment was deleted, False if it was not found.
+        """
+        async with self.get_db() as session:
+            session: AsyncSession
+            async with session.begin():
+                query = delete(Attachment).where(
+                    col(Attachment.attachment_id) == attachment_id
+                )
+                result = await session.execute(query)
+                return result.rowcount > 0
+
+    async def delete_attachments(self, attachment_ids: list[str]) -> int:
+        """Delete multiple attachments by their IDs.
+
+        Returns the number of attachments deleted.
+        """
+        if not attachment_ids:
+            return 0
+        async with self.get_db() as session:
+            session: AsyncSession
+            async with session.begin():
+                query = delete(Attachment).where(
+                    col(Attachment.attachment_id).in_(attachment_ids)
+                )
+                result = await session.execute(query)
+                return result.rowcount
+
     async def insert_persona(
         self,
         persona_id,