feat(model): add task defaults, job queries, and refine file/task DTOs

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

internal/model/cluster.go

@@ -1,6 +1,6 @@
 package model
 
-// NodeResponse is the API response for a node.
+// NodeResponse 是节点查询 API 响应。
 type NodeResponse struct {
 	// Identity
 	Name            string   `json:"name"`                         // 节点主机名
@@ -37,7 +37,7 @@ type NodeResponse struct {
 	ActiveFeatures string `json:"active_features,omitempty"` // 当前生效的特性标签 (只读)
 }
 
-// PartitionResponse is the API response for a partition.
+// PartitionResponse 是分区查询 API 响应。
 type PartitionResponse struct {
 	// Identity
 	Name    string   `json:"name"`              // 分区名称