feat(lyra): 为分类查询添加缓存并同步项目约定

- 实现分类列表缓存查询与故障降级
- 统一缓存键命名
- 同步日志、响应、依赖组装及测试约定
- 移除 postgres 占位目录

go/projects/lyra/internal/model/category.go

@@ -3,7 +3,11 @@ package model
 import (
 	"context"
 	"fmt"
+	"time"
+
 	"lyra/internal/cache"
+	"lyra/internal/pkg/constant"
+	"lyra/internal/util"
 
 	sq "github.com/Masterminds/squirrel"
 	"github.com/jmoiron/sqlx"
@@ -27,7 +31,17 @@ type defaultCategoryModel struct {
 func NewCategoryModel(db *sqlx.DB, cache *cache.Cache) CategoryModel {
 	return &defaultCategoryModel{db: db, cache: cache}
 }
+
+const categoryListCacheTTL = 5 * time.Minute
+
 func (m *defaultCategoryModel) FindAll(ctx context.Context) ([]*Category, error) {
+	cached, hit, err := m.cache.Get[[]*Category](ctx, constant.CategoryListCacheKey)
+	if err != nil {
+		util.Logger(ctx).Error("读取分类列表缓存失败", "key", constant.CategoryListCacheKey, "error", err)
+	}
+	if hit {
+		return cached, nil
+	}
 
 	query, args, err := sq.
 		Select("id", "slug", "title", "sort").
@@ -45,5 +59,12 @@ func (m *defaultCategoryModel) FindAll(ctx context.Context) ([]*Category, error)
 	if err != nil {
 		return nil, fmt.Errorf("数据库查询出错: %w", err)
 	}
-	return rows, err
+	if err := m.cache.Set(ctx, cache.Entry[[]*Category]{
+		Key:   constant.CategoryListCacheKey,
+		Value: rows,
+		TTL:   categoryListCacheTTL,
+	}); err != nil {
+		util.Logger(ctx).Error("写入分类列表缓存失败", "key", constant.CategoryListCacheKey, "error", err)
+	}
+	return rows, nil
 }