feat: chat folders, attachments, treeview backend - migration, models, routes

app/plugins/builtins/ai_assistant/schemas.py

@@ -169,6 +169,7 @@ class ChatSessionUpdate(BaseModel):
     title: str | None = Field(None, max_length=255)
     is_pinned: bool | None = None
     agent_id: str | None = None
+    folder_id: str | None = None
 
 
 class ChatSessionResponse(BaseModel):
@@ -179,6 +180,7 @@ class ChatSessionResponse(BaseModel):
     title: str
     is_pinned: bool
     is_sidebar: bool
+    folder_id: str | None = None
     created_at: datetime | None = None
     updated_at: datetime | None = None
 
@@ -203,6 +205,39 @@ class ChatSendRequest(BaseModel):
     agent_id: str | None = None  # override session agent
 
 
+# ─── Folders ───
+
+class ChatFolderCreate(BaseModel):
+    name: str = Field(..., min_length=1, max_length=255)
+    parent_id: str | None = None
+
+
+class ChatFolderUpdate(BaseModel):
+    name: str | None = Field(None, min_length=1, max_length=255)
+    parent_id: str | None = None
+
+
+class ChatFolderResponse(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+    id: str
+    name: str
+    parent_id: str | None = None
+    user_id: str
+    created_at: datetime | None = None
+
+
+# ─── Attachments ───
+
+class ChatAttachmentResponse(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+    id: str
+    message_id: str | None = None
+    session_id: str
+    filename: str
+    mime_type: str
+    size_bytes: int
+
+
 # ─── Tools ───
 
 class AIToolResponse(BaseModel):