接入Gitea Actions蓝绿部署：本地源码构建替代release下载，接入租户注册表迁移

- 新增docker/tinode/Dockerfile.build：从本仓库源码编译server/tinode-db/
  apply_hotgo_tenant_db，替代原Dockerfile下载GitHub release的方式(否则
  workbench/组织架构/会议等改造代码永远不会真正跑起来)
- config.template补上连接池设置(max_open_conns等，此前im_server踩过注册卡死
  的坑)，并启用tenant_db_routing+tenant_registry_db=hotgo，对应本仓库自带
  tinode.conf里的默认约定，单租户场景下会透明落回同一个tinode库
- entrypoint.sh在init-db之后追加执行apply-hotgo-tenant-db，幂等地建好/
  升级hotgo租户注册表及tinode库里的workbench/组织架构/会议/日报/信箱等新表
- 新增.gitea/workflows/deploy.yml，复用服务器上已有的蓝绿部署脚本

docker/tinode/entrypoint.sh

@@ -127,6 +127,15 @@ if [ $? -ne 0 ]; then
 	exit 1
 fi
 
+# Create/upgrade the hotgo tenant registry and the workbench/org/meetings/
+# reports/mailbox/etc. tables that init-db above does not manage. Idempotent
+# (IF NOT EXISTS / ON DUPLICATE KEY UPDATE throughout), safe to run every start.
+IM_MYSQL_DSN="${MYSQL_DSN}" ./apply-hotgo-tenant-db
+if [ $? -ne 0 ]; then
+	echo "./apply-hotgo-tenant-db failed. Quitting."
+	exit 1
+fi
+
 # If sample data was provided, try to find Tino password.
 if [ ! -z "$SAMPLE_DATA" ] ; then
 	grep "usr;tino;" $init_stdout > /botdata/tino-password