chore(spec): T1/T2 证据落库——备份三件套验证通过，翻译引擎缺口记录

- T1: pg_dump(halo_db) 237K 可恢复 + halo2 目录归档 404M/3577 项，verify_backup.sh 实跑通过
- T2: new-api 网关鉴权/模型端点可用；通用 chat 模型缺渠道（GLM 禁用、
  OpenRouter 仅特殊别名），需用户控制台启用，不阻塞 Phase 0

验证: bash .spec/specs/2026-10-24_add-blog-infra/evidence/verify_backup.sh
      （输出 backup verified: dump readable, tar entries=3577）

Co-authored-by: GLM-5.3

.spec/specs/2026-10-24_add-blog-infra/evidence/verify_backup.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+# Phase 0 T1 备份验收：dump 与目录归档三件套存在、非空、结构可读
+# 路径约定见 tasks.md T1；pg_restore 宿主缺失时经 postgres 容器兜底
+set -e
+B="$HOME/backups/blog/halo-20261024"
+test -s "$B/halo_db_20261024.dump"
+test -s "$B/halo2-dir-20261024.tar.gz"
+if command -v pg_restore >/dev/null 2>&1; then
+  pg_restore --list "$B/halo_db_20261024.dump" >/dev/null
+else
+  docker run --rm -v "$B:/b:ro" postgres:15.4 pg_restore --list /b/halo_db_20261024.dump >/dev/null
+fi
+N=$(tar tzf "$B/halo2-dir-20261024.tar.gz" | wc -l)
+[ "$N" -gt 3000 ]
+echo "backup verified: dump readable, tar entries=$N"