refactor(api): TOML 配置 SSOT、统一错误契约、Auth/事务加固与可观测性 (#33)

配置 SSOT（TOML + .env）
统一错误契约
Auth 与事务边界
Redis / Celery 可靠性:业务 Redis（DB/0）与 Celery broker/backend（DB/1）显式拆分；连接池、sync client
可观测性（OpenTelemetry + LGTM）

api/.agents/skills/redis-development/rules/rqe-index-management.md

@@ -0,0 +1,49 @@
+---
+title: Manage Indexes for Zero-Downtime Updates
+impact: MEDIUM
+impactDescription: Use aliases for seamless index updates
+tags: rqe, index, alias, management, reindex
+description: Manage Indexes for Zero-Downtime Updates
+alwaysApply: true
+---
+
+## Manage Indexes for Zero-Downtime Updates
+
+Use aliases to swap indexes without application changes.
+
+**Correct:** Use aliases for production indexes.
+
+```
+# Create versioned index
+FT.CREATE idx:products_v2 ON HASH PREFIX 1 product:
+    SCHEMA
+        name TEXT
+        category TAG SORTABLE
+        price NUMERIC SORTABLE
+
+# Point alias to new index
+FT.ALIASADD products idx:products_v2
+
+# Application queries use alias
+FT.SEARCH products "@category:{electronics}"
+
+# Later, swap to new version
+FT.ALIASUPDATE products idx:products_v3
+```
+
+**Useful management commands:**
+
+```
+# Check index info
+FT.INFO idx:products
+
+# Drop and recreate (non-blocking)
+FT.DROPINDEX idx:products
+FT.CREATE idx:products ...
+
+# List all indexes
+FT._LIST
+```
+
+Reference: [Redis Search Index Management](https://redis.io/docs/latest/develop/interact/search-and-query/administration/)
+