perf(cache): 三层缓存框架补强

- 新增 cache-framework skill，规范 RAM→Redis→DB 读路径、失效与 pub/sub
- 上传元数据 Otter+Redis 缓存与多节点失效；Auth Source 缓存与 pub/sub
- ListSystemConfigsByKeys 补 Redis 层；上传统计单事务；登录/Token 缓存预热
- cleanup 任务补 upload meta 失效钩子

internal/apps/user/routers.go

@@ -168,6 +168,8 @@ func Login(c *gin.Context) {
 		return
 	}
 
+	oauth.SetCachedUser(ctx, user.ID, user)
+
 	logger.InfoF(ctx, "[LoginAudit] successful login for user: %s, ID: %d, IP: %s", user.Username, user.ID, c.ClientIP())
 
 	listener.EmitAdminLoggedIn(ctx, user, c.ClientIP())