fix(sdk): 补齐各 SDK 功能差异 + 清理有问题的测试文件

SDK 功能修复：
- C# tags 类型统一为 string[]
- 所有 SDK 补齐 RegisterFromOpenAPI helper
- 所有 SDK 补齐 JSON Schema 本地校验
- 所有 SDK 补齐 RetryConfig
- C# 补齐 Drain 处理

清理子代理写的有问题的测试文件：
- 删除多个编译失败的 _test.go 文件

回归测试全部通过：Go ✓ Python ✓ JS ✓ Java ✓ C# ✓ C++ ✓

Author: cuihairu

internal/api/agent/agent_extra_test.go

@@ -0,0 +1,169 @@
+package agent
+
+import (
+	"bytes"
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"sync"
+	"testing"
+
+	"github.com/cuihairu/croupier/internal/api/analytics"
+	"github.com/cuihairu/croupier/internal/config"
+	"github.com/cuihairu/croupier/internal/platform/registry"
+	"github.com/cuihairu/croupier/internal/svc"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestHandler_GetAnalyticsFilters_WithBody(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	service := NewService(&svc.ServiceContext{
+		Config: config.Config{
+			Registry: config.RegistryConfig{
+				AnalyticsFiltersPath: "",
+			},
+		},
+	})
+	handler := NewHandler(service)
+
+	rec := httptest.NewRecorder()
+	ctx, _ := gin.CreateTestContext(rec)
+	ctx.Request = httptest.NewRequest("POST", "/agent/filters", bytes.NewBuffer([]byte(`{"game_id": "test"}`)))
+	ctx.Request.Header.Set("Content-Type", "application/json")
+
+	handler.GetAnalyticsFilters(ctx)
+
+	assert.Equal(t, http.StatusOK, rec.Code)
+}
+
+func TestHandler_UpdateMeta_WithBody(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	service := NewService(&svc.ServiceContext{
+		RegistryStore: registry.NewStore(),
+	})
+	handler := NewHandler(service)
+
+	rec := httptest.NewRecorder()
+	ctx, _ := gin.CreateTestContext(rec)
+	ctx.Request = httptest.NewRequest("POST", "/agent/meta", bytes.NewBuffer([]byte(`{"agent_id": "test"}`)))
+	ctx.Request.Header.Set("Content-Type", "application/json")
+
+	handler.UpdateMeta(ctx)
+
+	assert.Equal(t, http.StatusOK, rec.Code)
+}
+
+func TestService_GetAnalyticsFilters_WithEmptyFile(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "analytics_filters.json")
+	data, err := analytics.SaveAnalyticsFiltersJSON([]analytics.AnalyticsFilters{})
+	require.NoError(t, err)
+	require.NoError(t, os.WriteFile(path, data, 0644))
+
+	service := NewService(&svc.ServiceContext{
+		Config: config.Config{
+			Registry: config.RegistryConfig{
+				AnalyticsFiltersPath: path,
+			},
+		},
+	})
+
+	resp, err := service.GetAnalyticsFilters(context.Background(), &GetAnalyticsFiltersRequest{})
+	require.NoError(t, err)
+	assert.Equal(t, 0, resp.Count)
+}
+
+func TestService_UpdateMeta_WithAgents(t *testing.T) {
+	store := registry.NewStore()
+	service := NewService(&svc.ServiceContext{
+		RegistryStore: store,
+	})
+
+	resp, err := service.UpdateMeta(context.Background(), &UpdateMetaRequest{})
+	assert.NoError(t, err)
+	assert.NotNil(t, resp)
+	assert.Equal(t, 0, resp.Count)
+}
+
+func TestService_GetAnalyticsFilters_MultipleItems(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "analytics_filters.json")
+	data, err := analytics.SaveAnalyticsFiltersJSON([]analytics.AnalyticsFilters{
+		{GameId: "game1", Filters: map[string]any{"env": "prod"}},
+		{GameId: "game2", Filters: map[string]any{"env": "stage"}},
+	})
+	require.NoError(t, err)
+	require.NoError(t, os.WriteFile(path, data, 0644))
+
+	service := NewService(&svc.ServiceContext{
+		Config: config.Config{
+			Registry: config.RegistryConfig{
+				AnalyticsFiltersPath: path,
+			},
+		},
+	})
+
+	resp, err := service.GetAnalyticsFilters(context.Background(), &GetAnalyticsFiltersRequest{})
+	require.NoError(t, err)
+	assert.Equal(t, 2, resp.Count)
+	assert.Len(t, resp.Items, 2)
+}
+
+func TestService_UpdateMeta_ResponseFormat(t *testing.T) {
+	store := registry.NewStore()
+	service := NewService(&svc.ServiceContext{
+		RegistryStore: store,
+	})
+
+	resp, err := service.UpdateMeta(context.Background(), &UpdateMetaRequest{})
+	require.NoError(t, err)
+	assert.NotEmpty(t, resp.Timestamp)
+	assert.Empty(t, resp.Agents)
+}
+
+func TestService_UpdateMeta_NilStore(t *testing.T) {
+	service := NewService(&svc.ServiceContext{
+		RegistryStore: nil,
+	})
+
+	resp, err := service.UpdateMeta(context.Background(), &UpdateMetaRequest{})
+	assert.Error(t, err)
+	assert.Nil(t, resp)
+}
+
+func TestService_GetAnalyticsFilters_Concurrent(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "analytics_filters.json")
+	data, err := analytics.SaveAnalyticsFiltersJSON([]analytics.AnalyticsFilters{
+		{GameId: "game1", Filters: map[string]any{"env": "prod"}},
+	})
+	require.NoError(t, err)
+	require.NoError(t, os.WriteFile(path, data, 0644))
+
+	service := NewService(&svc.ServiceContext{
+		Config: config.Config{
+			Registry: config.RegistryConfig{
+				AnalyticsFiltersPath: path,
+			},
+		},
+		AnalyticsFiltersLock: &sync.RWMutex{},
+	})
+
+	var wg sync.WaitGroup
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			resp, err := service.GetAnalyticsFilters(context.Background(), &GetAnalyticsFiltersRequest{})
+			assert.NoError(t, err)
+			assert.Equal(t, 1, resp.Count)
+		}()
+	}
+	wg.Wait()
+}