feat(api): LlmSetting/Source 暴露 blocklist_tags,admin 编辑入口就绪

- schemas/source.SourceOut/In/Update 加 blocklist_tags
- admin.create_source 透传 blocklist_tags
- admin.update_source 走 setattr 通用,自动支持新字段
- admin_llm.get_settings 在 row=None 分支返回默认值时补 blocklist_tags=[]
- update_settings 走 setattr 通用,自动支持新字段

backend/app/schemas/source.py

@@ -25,6 +25,8 @@ class SourceOut(BaseModel):
     last_fetched_at: datetime | None = None
     last_status: str | None = None
     consecutive_failures: int = 0
+    # 源级屏蔽分类标签;与 llm_settings.blocklist_tags 合并后注入 classify prompt
+    blocklist_tags: list[str] = []
 
 
 class SourceIn(BaseModel):
@@ -40,6 +42,7 @@ class SourceIn(BaseModel):
     enabled: bool = True
     detail_selector: dict | None = None
     headers_json: dict | None = None
+    blocklist_tags: list[str] = []
 
 
 class SourceUpdate(BaseModel):
@@ -49,3 +52,4 @@ class SourceUpdate(BaseModel):
     fetch_interval_min: int | None = Field(default=None, ge=5, le=1440)
     region: str | None = None
     translate_to: str | None = None
+    blocklist_tags: list[str] | None = None