后端与全仓代码质量清理（golangci 扩展集 · 测试质量 · 并发安全 · 文档同步）

代码质量全量清理，零行为变化：golangci 扩展集 13 类 linter（gosec/modernize/perfsprint/canonicalheader/usestdlibvars/wastedassign/intrange/errorlint/forcetypeassert/recvcheck/exhaustive/unparam）全量修复，测试代码质量（testifylint/thelper/usetesting）25→0，frpc 进程生命周期真 bug（进程组击杀）、全仓 go test -race 6 类数据竞争（含 1 个生产竞争）、SPDX license 头补齐 131 文件、前端测试套件 next-intl 迁移后 44 失败→全绿、过期 swagger 文档重新生成、pnpm-workspace 构建审批。

Experiments: #2-#17, #18, #20, #21, #23
Metric: total_issues 108 → 8 (-92.6%)

internal/apps/openflare/pages/source_sync.go

@@ -9,7 +9,7 @@ import (
 	"errors"
 	"fmt"
 	"path"
-	"sort"
+	"slices"
 	"strings"
 	"sync"
 	"time"
@@ -611,7 +611,7 @@ func lockSourceDeploymentUploadsTx(
 	if hasIngest && ingestResult.Upload.ID != 0 && ingestResult.Upload.ID != target.UploadID {
 		uploadIDs = append(uploadIDs, ingestResult.Upload.ID)
 	}
-	sort.Slice(uploadIDs, func(i, j int) bool { return uploadIDs[i] < uploadIDs[j] })
+	slices.Sort(uploadIDs)
 	var records []model.Upload
 	if err := tx.Clauses(clause.Locking{Strength: pagesRowLockStrength}).
 		Where("id IN ?", uploadIDs).