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%)

pkg/cap/cap.go

@@ -215,7 +215,7 @@ func VerifyChallengeSolutions(token string, solutions []int, secret []byte, expe
 	}
 
 	tokenFnv := fnv1a(token)
-	for i := 0; i < payload.Count; i++ {
+	for i := range payload.Count {
 		idxStr := strconv.Itoa(i + 1)
 		saltSeed := fnv1aResume(tokenFnv, idxStr)
 		targetSeed := fnv1aResume(saltSeed, "d")
@@ -238,14 +238,14 @@ func VerifyChallengeSolutions(token string, solutions []int, secret []byte, expe
 func Solve(token string, count, size, difficulty int) []int {
 	solutions := make([]int, count)
 	tokenFnv := fnv1a(token)
-	for i := 0; i < count; i++ {
+	for i := range count {
 		idxStr := strconv.Itoa(i + 1)
 		saltSeed := fnv1aResume(tokenFnv, idxStr)
 		targetSeed := fnv1aResume(saltSeed, "d")
 		salt := prngFromHash(saltSeed, size)
 		target := prngFromHash(targetSeed, difficulty)
 
-		for nonce := 0; nonce < 1000000; nonce++ {
+		for nonce := range 1000000 {
 			hashInput := salt + strconv.Itoa(nonce)
 			hashBytes := sha256.Sum256([]byte(hashInput))
 			hashHex := hex.EncodeToString(hashBytes[:])

pkg/cap/prng.go

@@ -13,7 +13,7 @@ import (
 //nolint:mnd // FNV-1a 算法位移常量
 func fnv1a(str string) uint32 {
 	var hash uint32 = 2166136261
-	for i := 0; i < len(str); i++ {
+	for i := range len(str) {
 		hash ^= uint32(str[i])
 		hash += (hash << 1) + (hash << 4) + (hash << 7) + (hash << 8) + (hash << 24)
 	}
@@ -25,7 +25,7 @@ func fnv1a(str string) uint32 {
 //nolint:mnd // FNV-1a 算法位移常量
 func fnv1aResume(state uint32, str string) uint32 {
 	h := state
-	for i := 0; i < len(str); i++ {
+	for i := range len(str) {
 		h ^= uint32(str[i])
 		h += (h << 1) + (h << 4) + (h << 7) + (h << 8) + (h << 24)
 	}

pkg/cap/store.go

@@ -5,6 +5,7 @@ package cap
 
 import (
 	"context"
+	"errors"
 	"sync"
 	"time"
 
@@ -51,20 +52,21 @@ func NewMemoryStore(cleanupInterval time.Duration) *MemoryStore {
 func (s *MemoryStore) Get(_ context.Context, key string) (string, bool, error) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
-	return s.getLocked(key)
+	val, ok := s.getLocked(key)
+	return val, ok, nil
 }
 
 // getLocked is the internal helper – caller must hold s.mu.
-func (s *MemoryStore) getLocked(key string) (string, bool, error) {
+func (s *MemoryStore) getLocked(key string) (string, bool) {
 	item, found := s.items[key]
 	if !found {
-		return "", false, nil
+		return "", false
 	}
 	if time.Now().After(item.expiresAt) {
 		delete(s.items, key)
-		return "", false, nil
+		return "", false
 	}
-	return item.value, true, nil
+	return item.value, true
 }
 
 // Set 向 MemoryStore 写入指定 key 的值
@@ -92,7 +94,7 @@ func (s *MemoryStore) SetNX(_ context.Context, key string, val string, ttl time.
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
-	_, exists, _ := s.getLocked(key)
+	_, exists := s.getLocked(key)
 	if exists {
 		return false, nil
 	}
@@ -108,9 +110,9 @@ func (s *MemoryStore) GetAndDelete(_ context.Context, key string) (string, bool,
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
-	val, exists, err := s.getLocked(key)
-	if err != nil || !exists {
-		return "", false, err
+	val, exists := s.getLocked(key)
+	if !exists {
+		return "", false, nil
 	}
 	delete(s.items, key)
 	return val, true, nil
@@ -149,7 +151,7 @@ func NewRedisStore(client redis.UniversalClient) *RedisStore {
 // Get 从 RedisStore 获取指定 key 的值
 func (s *RedisStore) Get(ctx context.Context, key string) (string, bool, error) {
 	val, err := s.client.Get(ctx, key).Result()
-	if err == redis.Nil {
+	if errors.Is(err, redis.Nil) {
 		return "", false, nil
 	}
 	if err != nil {
@@ -176,7 +178,7 @@ func (s *RedisStore) SetNX(ctx context.Context, key string, val string, ttl time
 // GetAndDelete wraps Redis GETDEL (available since Redis 6.2).
 func (s *RedisStore) GetAndDelete(ctx context.Context, key string) (string, bool, error) {
 	val, err := s.client.GetDel(ctx, key).Result()
-	if err == redis.Nil {
+	if errors.Is(err, redis.Nil) {
 		return "", false, nil
 	}
 	if err != nil {