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

alembic/versions/20260311_2300_c1d2e3f4a5b6_cleanup_stale_provider_references.py

@@ -0,0 +1,116 @@
+"""cleanup stale provider references after provider deletion
+
+Revision ID: c1d2e3f4a5b6
+Revises: 9b7c6d5e4f3a
+Create Date: 2026-03-11 23:00:00.000000+00:00
+
+"""
+
+from __future__ import annotations
+
+import sqlalchemy as sa
+
+from alembic import op
+
+# revision identifiers, used by Alembic.
+revision = "c1d2e3f4a5b6"
+down_revision = "9b7c6d5e4f3a"
+branch_labels = None
+depends_on = None
+
+_users = sa.table(
+    "users",
+    sa.column("id", sa.String(36)),
+    sa.column("allowed_providers", sa.JSON()),
+)
+_api_keys = sa.table(
+    "api_keys",
+    sa.column("id", sa.String(36)),
+    sa.column("allowed_providers", sa.JSON()),
+)
+_user_preferences = sa.table(
+    "user_preferences",
+    sa.column("id", sa.String(36)),
+    sa.column("default_provider_id", sa.String(36)),
+)
+_video_tasks = sa.table(
+    "video_tasks",
+    sa.column("id", sa.String(36)),
+    sa.column("provider_id", sa.String(36)),
+    sa.column("endpoint_id", sa.String(36)),
+)
+_providers = sa.table("providers", sa.column("id", sa.String(36)))
+_provider_endpoints = sa.table("provider_endpoints", sa.column("id", sa.String(36)))
+
+
+def _load_valid_ids(conn: sa.Connection, table: sa.Table) -> set[str]:
+    return {str(row[0]) for row in conn.execute(sa.select(table.c.id)).fetchall() if row[0]}
+
+
+def _cleanup_allowed_providers(
+    conn: sa.Connection,
+    table: sa.Table,
+    valid_provider_ids: set[str],
+) -> None:
+    rows = conn.execute(
+        sa.select(table.c.id, table.c.allowed_providers).where(
+            table.c.allowed_providers.isnot(None)
+        )
+    ).fetchall()
+    for row_id, allowed_providers in rows:
+        if not isinstance(allowed_providers, list):
+            continue
+        filtered = [
+            provider_id for provider_id in allowed_providers if provider_id in valid_provider_ids
+        ]
+        if filtered == allowed_providers:
+            continue
+        conn.execute(table.update().where(table.c.id == row_id).values(allowed_providers=filtered))
+
+
+def _nullify_missing_fk(
+    conn: sa.Connection,
+    table: sa.Table,
+    id_column: sa.ColumnElement[str],
+    fk_column: sa.ColumnElement[str],
+    valid_ids: set[str],
+) -> None:
+    rows = conn.execute(sa.select(id_column, fk_column).where(fk_column.isnot(None))).fetchall()
+    invalid_row_ids = [row_id for row_id, fk_value in rows if fk_value not in valid_ids]
+    if not invalid_row_ids:
+        return
+    conn.execute(table.update().where(id_column.in_(invalid_row_ids)).values({fk_column.key: None}))
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+    valid_provider_ids = _load_valid_ids(conn, _providers)
+    valid_endpoint_ids = _load_valid_ids(conn, _provider_endpoints)
+
+    _cleanup_allowed_providers(conn, _users, valid_provider_ids)
+    _cleanup_allowed_providers(conn, _api_keys, valid_provider_ids)
+    _nullify_missing_fk(
+        conn,
+        _user_preferences,
+        _user_preferences.c.id,
+        _user_preferences.c.default_provider_id,
+        valid_provider_ids,
+    )
+    _nullify_missing_fk(
+        conn,
+        _video_tasks,
+        _video_tasks.c.id,
+        _video_tasks.c.provider_id,
+        valid_provider_ids,
+    )
+    _nullify_missing_fk(
+        conn,
+        _video_tasks,
+        _video_tasks.c.id,
+        _video_tasks.c.endpoint_id,
+        valid_endpoint_ids,
+    )
+
+
+def downgrade() -> None:
+    pass