feat: 0.2.27 - 抽离数据库基础设施模块

- 新增 ias-db crate，集中管理 PostgreSQL 连接池和 SQLx 迁移
- 迁移 ias-service/migrations 到 ias-db/migrations
- ias-main 改用 ias_db::connect_db()，ias-service 只接 PgPool
- 新增操作日志 HTTP 查询接口 (GET /v1/logs, GET /v1/logs/{id})
- 新增操作日志 Web 前端页面，支持按级别/模块/关键词筛选
- 消息队列关键节点增加操作日志写入
- ias-mail 新增 mark_remote_message_seen，IMAP 已读同步
- 工作流配置加载改为文件级容错 (load_configs_with_warnings)
- ias-context 工具调用说明更新为 query_api_docs + call_http_api
- 新增高德地图地理编码 HTTP 能力配置

模块版本: ias-db 0.1.0, ias-ai 0.1.14, ias-context 0.1.6, ias-http 0.1.15, ias-mail 0.1.16, ias-service 0.1.25, ias-main 0.2.27

ias-db/migrations/20260706012000_normalize_context_scope.sql

@@ -0,0 +1,29 @@
+UPDATE ias_long_term_memories
+SET scope_key = channel || ':' || account_id || ':' || from_user_id;
+
+UPDATE ias_context_sessions
+SET scope_key = channel || ':' || account_id || ':' || from_user_id;
+
+UPDATE ias_context_summaries AS summary
+SET scope_key = session.scope_key
+FROM ias_context_sessions AS session
+WHERE summary.source_session_id = session.id;
+
+WITH ranked AS (
+    SELECT
+        id,
+        ROW_NUMBER() OVER (
+            PARTITION BY scope_key
+            ORDER BY started_at DESC, id DESC
+        ) AS rank
+    FROM ias_context_sessions
+    WHERE ended_at IS NULL
+)
+UPDATE ias_context_sessions AS session
+SET
+    ended_at = last_message_at,
+    end_reason = 'scope_normalized',
+    summary = COALESCE(summary, '旧上下文 scope 合并时自动结束。')
+FROM ranked
+WHERE session.id = ranked.id
+    AND ranked.rank > 1;