feat(db): add migrations for RBAC, diagnostic, messaging, attendance, leave, invitation codes

- 0011: RBAC role flags and seed data

- 0012: diagnostic grade_id

- 0013: message recall

- 0014: message templates

- 0015: group messages and message reports/blocks

- 0016: invitation codes

- 0017: draft device sync

- 0018: attendance status reason

- 0019: attendance warning thresholds

- 0020: leave requests

- 0021: attendance period

drizzle/0013_message_recall.sql

@@ -0,0 +1,2 @@
+-- P2-4: 消息撤回功能（2 分钟窗口）
+ALTER TABLE `messages` ADD COLUMN `recalled_at` timestamp;