refactor: Antigravity/Codex 服务重构为插件化适配器架构

- 将 Antigravity 和 Codex 从独立模块迁移至 src/services/provider/adapters/ 插件体系
- 新增 provider_types 和 oauth_token 模块，移除 maintenance_scheduler 中的 OAuth 定时刷新
- 增强 admin API：扩展 keys 和 provider_query 端点，新增 dashboard 路由
- 大幅增强 ProviderDetailDrawer 组件，新增 AntigravityQuotaDialog
- 改进 handler 基类（chat/cli）和错误分类器
- 优化 fetch_scheduler 和 upstream_fetcher
- 前端 UI 组件清理和优化
- 更新测试以匹配新模块结构

tests/services/test_upstream_fetcher_antigravity_models.py

@@ -0,0 +1,69 @@
+from __future__ import annotations
+
+from unittest.mock import AsyncMock, patch
+
+import pytest
+
+from src.services.model.upstream_fetcher import UpstreamModelsFetchContext, fetch_models_for_key
+
+
+@pytest.mark.asyncio
+async def test_fetch_models_for_key_antigravity_parses_quota() -> None:
+    mock_resp = {
+        "models": {
+            "claude-sonnet-4": {
+                "displayName": "Claude Sonnet 4",
+                "quotaInfo": {"remainingFraction": 0.75, "resetTime": "2024-01-15T12:00:00Z"},
+            },
+            "gemini-2.5-pro": {
+                "displayName": "Gemini 2.5 Pro",
+                "quotaInfo": {"remainingFraction": 0.0},
+            },
+        }
+    }
+
+    ctx = UpstreamModelsFetchContext(
+        provider_type="antigravity",
+        api_key_value="tok",
+        format_to_endpoint={},
+        proxy_config=None,
+        auth_config={"project_id": "project-1"},
+    )
+
+    with patch(
+        "src.services.provider.adapters.antigravity.client.fetch_available_models",
+        AsyncMock(return_value=mock_resp),
+    ):
+        models, errors, ok, meta = await fetch_models_for_key(ctx, timeout_seconds=1.0)
+
+    assert ok is True
+    assert errors == []
+
+    ids = {m.get("id") for m in models}
+    assert "claude-sonnet-4" in ids
+    assert "gemini-2.5-pro" in ids
+
+    assert isinstance(meta, dict)
+    quota = meta["antigravity"]["quota_by_model"]
+    assert quota["claude-sonnet-4"]["remaining_fraction"] == 0.75
+    assert quota["claude-sonnet-4"]["used_percent"] == 25.0
+    assert quota["claude-sonnet-4"]["reset_time"] == "2024-01-15T12:00:00Z"
+    assert quota["gemini-2.5-pro"]["used_percent"] == 100.0
+
+
+@pytest.mark.asyncio
+async def test_fetch_models_for_key_antigravity_requires_project_id() -> None:
+    ctx = UpstreamModelsFetchContext(
+        provider_type="antigravity",
+        api_key_value="tok",
+        format_to_endpoint={},
+        proxy_config=None,
+        auth_config={},
+    )
+
+    models, errors, ok, meta = await fetch_models_for_key(ctx, timeout_seconds=1.0)
+
+    assert ok is False
+    assert models == []
+    assert meta is None
+    assert any("project_id" in e for e in errors)