fix(ws2-migration): 補 enum types + 執行 prod migration

- CREATE TYPE approvalstatus / risklevel（SQLAlchemy native_enum）
- approval_records 已在 prod awoooi_prod 建立
  - telegram_chat_id BIGINT（支援 -1003711974679）
  - status approvalstatus enum（非 VARCHAR）
- awoooi_migrator 角色需 superuser 才能建，留 backlog

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/api/migrations/adr093_notification_routing.sql

@@ -17,14 +17,23 @@ GRANT CONNECT ON DATABASE awoooi_prod TO awoooi_migrator;
 GRANT USAGE ON SCHEMA public TO awoooi_migrator;
 GRANT CREATE ON SCHEMA public TO awoooi_migrator;
 
+-- SQLAlchemy native enum types（SQLEnum 預設 native_enum=True）
+DO $$ BEGIN
+    CREATE TYPE approvalstatus AS ENUM ('pending','approved','rejected','expired','execution_success','execution_failed');
+EXCEPTION WHEN duplicate_object THEN NULL; END $$;
+
+DO $$ BEGIN
+    CREATE TYPE risklevel AS ENUM ('low','medium','high','critical');
+EXCEPTION WHEN duplicate_object THEN NULL; END $$;
+
 -- approval_records 主表（全新建立，直接用 BIGINT）
 -- 注意：test schema setup_test_schema.sql 同步更新為 BIGINT
 CREATE TABLE IF NOT EXISTS approval_records (
     id                  VARCHAR(36)      PRIMARY KEY,
     action              VARCHAR(500)     NOT NULL,
     description         TEXT             NOT NULL,
-    status              VARCHAR(20)      NOT NULL DEFAULT 'PENDING',
-    risk_level          VARCHAR(20)      NOT NULL,
+    status              approvalstatus   NOT NULL DEFAULT 'pending',
+    risk_level          risklevel        NOT NULL,
     required_signatures INTEGER          DEFAULT 1,
     current_signatures  INTEGER          DEFAULT 0,
     signatures          JSON             DEFAULT '[]',