chore(lint): unify formatting on golangci-lint fmt (gofumpt), uncap issue reporting, fix gofumpt drift

- make format 现在与 code-check 使用同一格式化器（golangci-lint fmt），消除 goimports -local 与 gofumpt 的格式拉锯
- .golangci.yml 关闭默认 50/3 截断，完整上报所有问题（只增强不弱化）
- 全库 gofumpt 规范化（203 files, 纯格式无行为变更）

backend/pkg/cache/disk/cache.go

@@ -26,7 +26,7 @@ const (
 	headerSize        = 8 // 8 bytes metadata prefix for expiration UnixNano timestamp
 	defaultMaxSizeMB  = 100
 	defaultTTLMinutes = 60
-	cacheDirPerm      = 0750
+	cacheDirPerm      = 0o750
 
 	// DefaultExpiration applies the cache-wide default TTL.
 	DefaultExpiration time.Duration = 0
@@ -284,7 +284,7 @@ func (c *Cache) Status() Status {
 }
 
 // UpdatePolicy dynamically updates policies.
-func (c *Cache) UpdatePolicy(maxSizeMB int64, ttlMinutes int64, lruEnabled bool) {
+func (c *Cache) UpdatePolicy(maxSizeMB, ttlMinutes int64, lruEnabled bool) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 

backend/pkg/cache/ram/manager.go

@@ -31,7 +31,7 @@ type CacheItem struct {
 // Loader is an interface that the cache client must implement to handle database retrieval.
 type Loader interface {
 	LoadAll(ctx context.Context, configType string) ([]CacheItem, error)
-	LoadOne(ctx context.Context, configType string, key string) (CacheItem, error)
+	LoadOne(ctx context.Context, configType, key string) (CacheItem, error)
 }
 
 type cacheEntry struct {
@@ -59,7 +59,7 @@ func getWriteLock(configType string) *sync.Mutex {
 
 // Get retrieves a cache item from the local cache store, checking for expiration.
 // Reads are completely lock-free because maps stored in Otter are immutable.
-func Get(configType string, key string) (CacheItem, bool) {
+func Get(configType, key string) (CacheItem, bool) {
 	m, ok := managerCache.GetIfPresent(configType)
 	if !ok {
 		return CacheItem{}, false
@@ -80,7 +80,7 @@ func Get(configType string, key string) (CacheItem, bool) {
 	return entry.item, true
 }
 
-func deleteKeyIfExpired(configType string, key string, expireAt time.Time) {
+func deleteKeyIfExpired(configType, key string, expireAt time.Time) {
 	lock := getWriteLock(configType)
 	lock.Lock()
 	defer lock.Unlock()
@@ -138,7 +138,7 @@ func Set(item CacheItem) {
 
 // Delete removes a single item from the local cache store.
 // Writes are protected by a fine-grained lock per configType.
-func Delete(configType string, key string) {
+func Delete(configType, key string) {
 	lock := getWriteLock(configType)
 	lock.Lock()
 	defer lock.Unlock()
@@ -196,7 +196,7 @@ func GetTypeItems(configType string) []CacheItem {
 }
 
 // Refresh reloads configuration cache from database via the Loader.
-func Refresh(ctx context.Context, configType string, key string, loader Loader) error {
+func Refresh(ctx context.Context, configType, key string, loader Loader) error {
 	if configType == "" {
 		return errors.New("type is required")
 	}