feat: per-task model/effort/approval + relay models endpoint (#59)

Co-authored-by: host <host@test.local>

cloud/worker.py

@@ -225,6 +225,10 @@ def _task_from_row(row):
         "goal": _col("goal"),
         "verify_command": _col("verify_command"),
         "goal_max_rounds": _col("goal_max_rounds"),
+        # 任务级选项：老行缺列时 None = 跟随配置（见 server 侧）。
+        "model": _col("model"),
+        "effort": _col("effort"),
+        "approval": _col("approval"),
     }
 
 
@@ -539,7 +543,10 @@ class Worker:
                 "pr_number": "INTEGER", "goal": "TEXT",
                 "verify_command": "TEXT",
                 "goal_max_rounds": "INTEGER",
-                "worktree_host": "TEXT"}.items():
+                "worktree_host": "TEXT",
+                "model": "TEXT",
+                "effort": "TEXT",
+                "approval": "TEXT"}.items():
             if name not in cols:
                 try:
                     conn.execute(