feat: 添加回路名称字段并实现元数据缓存查询

在 RCU 事件处理中新增回路名称（loop_name）字段，用于标识具体设备回路。
- 在 rcu_action_events 表中添加 loop_name 字段
- 新增项目元数据缓存模块，每日从 temporary_project 表刷新房间与回路信息
- 处理消息时，根据 device_id、dev_addr 等字段查询缓存获取回路名称
- 若缓存未命中，则根据设备类型规则生成兜底名称
- 更新环境变量、文档及测试用例以适配新功能

openspec/changes/feature-loop-name-enrichment.md

@@ -0,0 +1,32 @@
+# Feature: Loop Name Enrichment
+
+**Status**: Proposed
+**Date**: 2026-02-02
+
+## Summary
+Enrich incoming RCU action events with `loop_name` by looking up metadata from `temporary_project` tables. This allows easier identification of specific device loops (e.g., "Main Chandelier") in the event log.
+
+## Requirements
+1.  **Cache Mechanism**: 
+    - Load `rooms` and `loops` data from `temporary_project` schema into memory.
+    - Refresh cache daily at 1:00 AM.
+2.  **Enrichment**:
+    - For each incoming event, look up `loop_name` using `device_id` and `dev_addr`.
+    - `device_id` -> `room_type_id` (via `rooms` table).
+    - `room_type_id` + `dev_addr` -> `loop_name` (via `loops` table).
+3.  **Storage**:
+    - Store `loop_name` in `rcu_action_events` table.
+
+## Ambiguity Resolution
+- The requirement mentioned matching `dev_type` to find the loop. However, standard RCU addressing uses `dev_addr` (and `dev_loop`). We assume `loops.loop_address` corresponds to the packet's `dev_addr` (converted to string).
+- We will attempt to match `dev_addr` against `loop_address`.
+
+## Schema Changes
+- **Table**: `rcu_action.rcu_action_events`
+- **Column**: `loop_name` (VARCHAR(255), Nullable)
+
+## Implementation Plan
+1.  **Database**: Update `init_db.sql` and `databaseManager.js`.
+2.  **Cache**: Create `src/cache/projectMetadata.js`.
+3.  **Processor**: Integrate cache lookup in `src/processor/index.js`.
+4.  **Lifecycle**: Initialize cache in `src/index.js`.

openspec/project.md

@@ -12,6 +12,9 @@ Backend service for processing RCU action events from Kafka, parsing them, and s
   - **Error Handling**: Redis List (`error_queue`) for failed messages + Retry mechanism
 - **Output**: PostgreSQL Table (`rcu_action_events`)
 
+## Features
+- **Loop Name Enrichment**: Enriches event data with `loop_name` by matching `device_id` and `dev_addr` against metadata cached from `temporary_project` tables (refreshed daily).
+
 ## Configuration (Environment Variables)
 The project is configured via `.env`. Key variables:
 - **Kafka**: `KAFKA_BROKERS`, `KAFKA_TOPIC`, `KAFKA_SASL_USERNAME`, `KAFKA_SASL_PASSWORD`