feat(providers): provider 摘要列表排序增加启用状态优先

后端查询和前端展示均按 is_active 降序、priority 升序、created_at 升序排列，
确保已启用的 provider 始终排在前面。

tests/services/test_provider_summary_ordering.py

@@ -0,0 +1,77 @@
+from __future__ import annotations
+
+from datetime import datetime, timedelta, timezone
+
+from sqlalchemy import Boolean, Column, DateTime, Integer, String, create_engine, select
+from sqlalchemy.orm import Session, declarative_base
+
+from src.api.admin.providers.summary import _provider_summary_ordering
+
+Base = declarative_base()
+
+
+class DemoProvider(Base):
+    __tablename__ = "demo_providers"
+
+    id = Column(String(36), primary_key=True)
+    name = Column(String(100), nullable=False)
+    is_active = Column(Boolean, nullable=False)
+    provider_priority = Column(Integer, nullable=False)
+    created_at = Column(DateTime(timezone=True), nullable=False)
+
+
+def test_provider_summary_ordering_puts_inactive_providers_last() -> None:
+    engine = create_engine("sqlite:///:memory:")
+    try:
+        Base.metadata.create_all(engine)
+
+        with Session(engine) as db:
+            base_time = datetime(2026, 3, 15, tzinfo=timezone.utc)
+            db.add_all(
+                [
+                    DemoProvider(
+                        id="inactive-top-priority",
+                        name="inactive-top-priority",
+                        is_active=False,
+                        provider_priority=0,
+                        created_at=base_time,
+                    ),
+                    DemoProvider(
+                        id="active-lower-priority",
+                        name="active-lower-priority",
+                        is_active=True,
+                        provider_priority=20,
+                        created_at=base_time + timedelta(seconds=1),
+                    ),
+                    DemoProvider(
+                        id="active-higher-priority-newer",
+                        name="active-higher-priority-newer",
+                        is_active=True,
+                        provider_priority=5,
+                        created_at=base_time + timedelta(seconds=3),
+                    ),
+                    DemoProvider(
+                        id="active-higher-priority-older",
+                        name="active-higher-priority-older",
+                        is_active=True,
+                        provider_priority=5,
+                        created_at=base_time + timedelta(seconds=2),
+                    ),
+                ]
+            )
+            db.commit()
+
+            ordered = (
+                db.execute(select(DemoProvider).order_by(*_provider_summary_ordering(DemoProvider)))
+                .scalars()
+                .all()
+            )
+
+        assert [provider.id for provider in ordered] == [
+            "active-higher-priority-older",
+            "active-higher-priority-newer",
+            "active-lower-priority",
+            "inactive-top-priority",
+        ]
+    finally:
+        engine.dispose()