F1: add reusable task backend resources and migrate task tools

backend/schemas.py

@@ -21,7 +21,7 @@ AssistantType = Literal["prompt", "workflow", "dify", "fastgpt"]
 SUPPORTED_ASSISTANT_TYPES = get_args(AssistantType)
 TurnEndStrategy = Literal["silence", "smart_turn"]
 KnowledgeRetrievalMode = Literal["automatic", "on_demand"]
-ToolType = Literal["http", "mcp", "client", "task"]
+ToolType = Literal["http", "mcp", "client"]
 ToolStatus = Literal["active", "archived", "draft"]
 McpServerStatus = Literal["active", "archived", "draft"]
 McpTransport = Literal["streamable_http", "sse"]
@@ -180,6 +180,12 @@ class ToolBinding(CamelModel):
     result_assignments: dict[str, str] = Field(default_factory=dict)
 
 
+class AssistantTaskBackendBinding(CamelModel):
+    backend_id: str = Field(min_length=1, max_length=40)
+    instruction_source: ValueSource = Field(default_factory=ModelValueSource)
+    instructions: str = Field(default="", max_length=12000)
+
+
 class StartupAction(CamelModel):
     id: str = Field(min_length=1, max_length=64, pattern=r"^[A-Za-z][A-Za-z0-9_-]*$")
     phase: Literal["preflight", "opening"] = "opening"
@@ -233,6 +239,7 @@ class AssistantUpsert(CamelModel):
         default_factory=KnowledgeRetrievalConfig
     )
     tool_bindings: list[ToolBinding] = Field(default_factory=list)
+    task_backend: AssistantTaskBackendBinding | None = None
     built_in_tools: "BuiltInTools" = Field(default_factory=lambda: BuiltInTools())
 
     # 瘦类型专属(真列);按 type 取用,无关字段写入时清零
@@ -262,6 +269,8 @@ class AssistantUpsert(CamelModel):
 
     @model_validator(mode="after")
     def _strip_irrelevant_fields(self):
+        if self.task_backend and (self.type != "prompt" or self.runtime_mode != "pipeline"):
+            raise ValueError("任务后端仅支持提示词 Pipeline")
         allowed = ALLOWED_FIELDS[self.type]
         for field in ("prompt", "api_url", "api_key", "app_id"):
             if field not in allowed:
@@ -474,37 +483,11 @@ class McpToolDefinition(CamelModel):
     config: McpToolConfig
 
 
-class TaskToolConfig(CamelModel):
-    provider: Literal["opencode"] = "opencode"
-    url: str = Field(min_length=1, max_length=2048)
-    directory: str = Field(min_length=1, max_length=2048)
-    username: str = Field(default="opencode", max_length=128)
-    timeout_seconds: int = Field(default=600, ge=30, le=7200)
-    allow_interruptions: Literal[True] = True
-    execution_mode: Literal["immediate"] = "immediate"
-
-    @field_validator("url")
-    @classmethod
-    def validate_task_url(cls, value: str) -> str:
-        from urllib.parse import urlsplit
-        parsed = urlsplit(value)
-        if parsed.scheme not in {"http", "https"} or not parsed.hostname or parsed.username or parsed.password or parsed.query or parsed.fragment:
-            raise ValueError("任务服务须使用不含凭证、查询参数的 HTTP(S) 地址")
-        return value.rstrip("/")
-
-
-class TaskToolDefinition(CamelModel):
-    schema_version: int = 2
-    type: Literal["task"] = "task"
-    config: TaskToolConfig
-
-
 ToolDefinition = Annotated[
     Union[
         HttpToolDefinition,
         ClientToolDefinition,
         McpToolDefinition,
-        TaskToolDefinition,
     ],
     Field(discriminator="type"),
 ]