feat: 添加视频生成功能增强和多维度计费系统适配

- 视频生成: 增强 video_handler，重构 task_poller，新增 telemetry
- 计费系统: 适配新的 signature 格式，支持 video 任务类型回退
- 数据库迁移: 添加 api_family/endpoint_kind 字段和 video_formats

tests/services/test_video_task_poller.py

@@ -0,0 +1,45 @@
+from types import SimpleNamespace
+from unittest.mock import AsyncMock, MagicMock
+
+import pytest
+
+from src.core.api_format.conversion.internal_video import InternalVideoPollResult, VideoStatus
+from src.services.video.task_poller import VideoTaskPollerService
+
+
+@pytest.mark.asyncio
+async def test_poll_task_status_routes_gemini_video_to_gemini(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    poller = VideoTaskPollerService()
+
+    task = SimpleNamespace(
+        endpoint_id="e1",
+        key_id="k1",
+        provider_api_format="gemini:video",
+        external_task_id="operations/123",
+    )
+    endpoint = SimpleNamespace(id="e1", base_url="https://example.com", api_format="gemini:video")
+    key = SimpleNamespace(id="k1", api_key="enc")
+
+    monkeypatch.setattr(poller, "_get_endpoint", lambda _db, _id: endpoint)
+    monkeypatch.setattr(poller, "_get_key", lambda _db, _id: key)
+    monkeypatch.setattr(
+        "src.services.video.task_poller.crypto_service.decrypt", lambda _v: "decrypted"
+    )
+
+    auth_info = SimpleNamespace(auth_header="authorization", auth_value="Bearer x")
+    monkeypatch.setattr(
+        "src.services.video.task_poller.get_provider_auth",
+        AsyncMock(return_value=auth_info),
+    )
+
+    poll_gemini = AsyncMock(return_value=InternalVideoPollResult(status=VideoStatus.PROCESSING))
+    poll_openai = AsyncMock(return_value=InternalVideoPollResult(status=VideoStatus.PROCESSING))
+    monkeypatch.setattr(poller, "_poll_gemini", poll_gemini)
+    monkeypatch.setattr(poller, "_poll_openai", poll_openai)
+
+    result = await poller._poll_task_status(MagicMock(), task)
+    assert result.status == VideoStatus.PROCESSING
+    assert poll_gemini.await_count == 1
+    assert poll_openai.await_count == 0