fix: golangci-lint 零告警通过 (57→0) + gofumpt/goimports 全量格式化

## CI 修复 (P0/P1)

P0 — 编译阻塞:
  - interfaces.go: postUseCase ISP 接口移除不用的 Create/Update/Delete

P1 — 必须修复:
  - ST1000: 为 13 个包添加包注释 (common/config/model/service/...)
  - ST1005: redis_store.go 全部错误消息改为小写开头
  - errcheck (19处): defer Close()→闭包忽略, notifier.Create→_=, r.Run→检查error
  - errorlint (9处): switch-on-error→errors.Is 链, ==→errors.Is
  - ST1020/ST1022: 导出符号注释以符号名开头

P2 — 安全评审:
  - gosec (12处): G203/G301/G304/G306 添加 nolint 注释并附理由

P3 — 清理:
  - unused: 移除 hasUnicode/energyStore/current/energyAdminUseCase
  - gofumpt + goimports 全量格式化 (35+ 文件)

internal/controller/energy_controller.go

@@ -1,6 +1,7 @@
 package controller
 
 import (
+	"errors"
 	"net/http"
 	"strconv"
 
@@ -39,18 +40,17 @@ func (ec *EnergyController) Energize(c *gin.Context) {
 
 	expGained, actualAmount, err := ec.energySvc.Energize(uid, req.PostID, req.Amount)
 	if err != nil {
-		switch err {
-		case common.ErrPostNotFound:
+		if errors.Is(err, common.ErrPostNotFound) {
 			common.Error(c, http.StatusNotFound, "文章不存在")
-		case common.ErrCannotEnergizeSelf:
+		} else if errors.Is(err, common.ErrCannotEnergizeSelf) {
 			common.Error(c, http.StatusBadRequest, "不能给自己的文章赋能")
-		case common.ErrInsufficientEnergy:
+		} else if errors.Is(err, common.ErrInsufficientEnergy) {
 			common.Error(c, http.StatusBadRequest, "域能不足，可通过每日签到或创作被赋能获取")
-		case common.ErrEnergizeLimitReached:
+		} else if errors.Is(err, common.ErrEnergizeLimitReached) {
 			common.Error(c, http.StatusBadRequest, "对该文章赋能已达上限")
-		case common.ErrInvalidEnergyAmount:
+		} else if errors.Is(err, common.ErrInvalidEnergyAmount) {
 			common.Error(c, http.StatusBadRequest, "无效的赋能数量")
-		default:
+		} else {
 			common.Error(c, http.StatusInternalServerError, "赋能失败")
 		}
 		return
@@ -136,13 +136,13 @@ func (ec *EnergyController) GetEnergyLogs(c *gin.Context) {
 
 // EnergyLogView 前端展示用的域能流水视图
 type EnergyLogView struct {
-	ID          uint    `json:"id"`
-	Amount      int     `json:"amount"`
+	ID            uint    `json:"id"`
+	Amount        int     `json:"amount"`
 	AmountDisplay float64 `json:"amount_display"`
-	Type        string  `json:"type"`
-	TypeName    string  `json:"type_name"`
-	Description string  `json:"description"`
-	CreatedAt   string  `json:"created_at"`
+	Type          string  `json:"type"`
+	TypeName      string  `json:"type_name"`
+	Description   string  `json:"description"`
+	CreatedAt     string  `json:"created_at"`
 }
 
 func toEnergyLogViews(logs []model.EnergyLog) []EnergyLogView {