feat: route background ai workloads by model

ai_knowledge_base_v2/apps/backend/app/schemas/admin.py

@@ -26,6 +26,17 @@ class AdminRead(ORMModel):
     status: int
 
 
+class CostBreakdownItem(BaseModel):
+    scene: str
+    modelName: str
+    requestCount: int
+    inputToken: int
+    outputToken: int
+    totalToken: int
+    estimatedCost: float
+    currency: str | None = None
+
+
 class DashboardStats(BaseModel):
     userCount: int
     sessionCount: int
@@ -37,6 +48,7 @@ class DashboardStats(BaseModel):
     totalToken: int
     estimatedCost: float | None = None
     costCurrency: str | None = None
+    costBreakdown: list[CostBreakdownItem] = Field(default_factory=list)
 
 
 class AdminUserUpdateRequest(BaseModel):
@@ -175,6 +187,11 @@ class ModelSaveRequest(BaseModel):
 
 class EnableModelRequest(BaseModel):
     modelId: int
+    enabled: int = Field(default=1, ge=0, le=1)
+
+
+class DefaultModelRequest(BaseModel):
+    modelId: int
 
 
 class SystemConfigSaveRequest(BaseModel):