feat: Provider 异步删除、可配置密码策略、Hub 超时优化及多项改进

- 新增 Provider 异步删除任务系统，后台分阶段删除子资源并清理残留引用
- 新增可配置密码策略等级（weak/medium/strong），支持系统设置面板调整
- aether-hub 升级至 0.1.4，idle timeout 支持禁用（设为 0），worker 默认超时调整为 120s
- OAuth 手动续期增加 Redis 分布式锁，防止并发刷新冲突
- ProxyNode 心跳检测改为 asyncio.to_thread，避免阻塞事件循环
- 删除 ModelMultiSelect 和 useInvalidModels，MultiSelect 组件通用化
- 明确 allowed_providers/allowed_api_formats 的 NULL 与空数组语义
- 前端 StandaloneKeyFormDialog、UserFormDialog 等多处 UI 优化
- 新增 Alembic 迁移脚本清理 Provider 删除后的残留引用
- 补充相关测试用例

tests/services/test_provider_delete_cleanup.py

@@ -0,0 +1,159 @@
+from __future__ import annotations
+
+from types import SimpleNamespace
+from unittest.mock import MagicMock
+
+import pytest
+
+from src.services.provider import delete_cleanup as cleanup_module
+from src.services.provider.delete_cleanup import (
+    delete_provider_tree,
+    prune_allowed_provider_list,
+    prune_allowed_provider_refs,
+)
+
+
+def _query_mock(
+    *,
+    rows: list[object] | None = None,
+    update_count: int | None = None,
+    delete_count: int | None = None,
+) -> MagicMock:
+    query = MagicMock()
+    filtered = query.filter.return_value
+    if rows is not None:
+        filtered.all.return_value = rows
+    if update_count is not None:
+        filtered.update.return_value = update_count
+    if delete_count is not None:
+        filtered.delete.return_value = delete_count
+    return query
+
+
+def test_prune_allowed_provider_list_removes_target_and_normalizes_empty() -> None:
+    next_allowed, changed = prune_allowed_provider_list(["provider-a", "provider-b"], "provider-a")
+
+    assert changed is True
+    assert next_allowed == ["provider-b"]
+
+    next_allowed, changed = prune_allowed_provider_list(["provider-a"], "provider-a")
+
+    assert changed is True
+    assert next_allowed == []
+
+
+def test_prune_allowed_provider_refs_updates_matching_records_only() -> None:
+    records = [
+        SimpleNamespace(allowed_providers=["provider-a", "provider-b"]),
+        SimpleNamespace(allowed_providers=["provider-b"]),
+        SimpleNamespace(allowed_providers=None),
+    ]
+
+    updated = prune_allowed_provider_refs(records, "provider-a")
+
+    assert updated == 1
+    assert records[0].allowed_providers == ["provider-b"]
+    assert records[1].allowed_providers == ["provider-b"]
+    assert records[2].allowed_providers is None
+
+
+@pytest.mark.asyncio
+async def test_cleanup_deleted_provider_references_cleans_large_fanout_tables(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    db = MagicMock()
+
+    user_records = [SimpleNamespace(allowed_providers=["provider-a", "provider-b"])]
+    api_key_records = [SimpleNamespace(allowed_providers=["provider-a"])]
+    key_cleanup_calls: list[list[str]] = []
+
+    monkeypatch.setattr(
+        cleanup_module,
+        "cleanup_key_references",
+        lambda _db, key_ids: key_cleanup_calls.append(list(key_ids)),
+    )
+
+    db.query.side_effect = [
+        _query_mock(rows=[("endpoint-1",), ("endpoint-2",)]),
+        _query_mock(rows=[("key-1",), ("key-2",)]),
+        _query_mock(rows=user_records),
+        _query_mock(rows=api_key_records),
+        _query_mock(update_count=2),
+        _query_mock(update_count=3),
+        _query_mock(update_count=4),
+        _query_mock(update_count=5),
+        _query_mock(update_count=6),
+        _query_mock(delete_count=7),
+        _query_mock(delete_count=8),
+    ]
+
+    stats = cleanup_module.cleanup_deleted_provider_references(db, "provider-a")
+
+    assert stats == {
+        "users": 1,
+        "api_keys": 1,
+        "user_preferences": 2,
+        "usage_provider": 3,
+        "usage_endpoint": 5,
+        "video_tasks_provider": 4,
+        "video_tasks_endpoint": 6,
+        "request_candidates_provider": 8,
+        "request_candidates_endpoint": 7,
+    }
+    assert user_records[0].allowed_providers == ["provider-b"]
+    assert api_key_records[0].allowed_providers == []
+    assert key_cleanup_calls == [["key-1", "key-2"]]
+
+
+def test_delete_provider_tree_deletes_children_before_provider(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    db = MagicMock()
+
+    cleanup_mock = MagicMock(
+        return_value={
+            "users": 1,
+            "api_keys": 2,
+            "user_preferences": 3,
+            "usage_provider": 4,
+            "usage_endpoint": 5,
+            "video_tasks_provider": 6,
+            "video_tasks_endpoint": 7,
+            "request_candidates_provider": 8,
+            "request_candidates_endpoint": 9,
+        }
+    )
+    monkeypatch.setattr(cleanup_module, "cleanup_deleted_provider_references", cleanup_mock)
+
+    db.query.side_effect = [
+        _query_mock(rows=[("endpoint-1",), ("endpoint-2",)]),
+        _query_mock(rows=[("key-1",), ("key-2",), ("key-3",)]),
+        _query_mock(delete_count=10),
+        _query_mock(delete_count=11),
+        _query_mock(delete_count=12),
+        _query_mock(delete_count=13),
+        _query_mock(delete_count=14),
+        _query_mock(delete_count=1),
+    ]
+
+    stats = delete_provider_tree(db, "provider-a")
+
+    cleanup_mock.assert_called_once_with(
+        db,
+        "provider-a",
+        endpoint_ids=["endpoint-1", "endpoint-2"],
+        key_ids=["key-1", "key-2", "key-3"],
+    )
+    assert stats == {
+        "cleanup": cleanup_mock.return_value,
+        "deleted": {
+            "api_key_mappings": 10,
+            "usage_tracking": 11,
+            "models": 12,
+            "api_keys": 13,
+            "endpoints": 14,
+            "providers": 1,
+        },
+        "key_count": 3,
+        "endpoint_count": 2,
+    }