docs: add upgrade recovery guide and troubleshooting table

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

README.md

@@ -1,6 +1,6 @@
 # memory-continuity
 
-**Current release:** `v2.1.0`
+**Current release:** `v2.3.0`
 
 OpenClaw **lifecycle plugin** for short-term working continuity. Preserves structured in-flight work state across `/new`, reset, gateway restarts, model fallback, and context compaction.
 
@@ -157,6 +157,47 @@ scp $WORKSPACE/memory/CURRENT_STATE.md newhost:$WORKSPACE/memory/
 
 No database, no vector embeddings, no API keys to transfer.
 
+## OpenClaw 升级后恢复
+
+OpenClaw 升级（`npm update -g openclaw`）**不会覆盖** `~/.openclaw/openclaw.json` 用户配置。但如果插件行为异常，按以下步骤排查和恢复：
+
+### 快速诊断
+
+```bash
+# 检查插件是否加载
+openclaw gateway restart 2>&1 | grep memory-continuity
+# 应输出: [memory-continuity] Plugin registered successfully
+
+# 检查配置是否完整
+cat ~/.openclaw/openclaw.json | grep -A2 memory-continuity
+```
+
+### 常见故障与恢复
+
+| 症状 | 原因 | 恢复方法 |
+|------|------|---------|
+| 启动日志无 `Plugin registered` | 插件文件缺失或配置丢失 | 重跑 `bash scripts/post-install.sh` |
+| `plugins.allow is empty` 警告 | `openclaw.json` 中 `plugins.allow` 被清空 | 添加 `"plugins.allow": ["memory-continuity"]` |
+| `loaded without provenance` 警告 | `plugins.installs` 记录丢失 | 添加 `"plugins.installs": {"memory-continuity": {"source": "path"}}` |
+| 新版本改了钩子 API | OpenClaw breaking change | 查看 [CHANGELOG](CHANGELOG.md)，更新 `index.js` |
+| 状态不恢复但无报错 | Session 缓存了旧的 skillsSnapshot | `/new` 开新 session，或重跑 `post-install.sh`（会清缓存） |
+
+### 一键恢复
+
+出现任何问题，重跑安装脚本即可（幂等，可重复执行）：
+
+```bash
+cd ~/.openclaw/projects/memory-continuity   # 或你 clone 的位置
+git pull                                     # 拉取最新版本
+bash scripts/post-install.sh                 # 重新安装 + 重启 gateway
+```
+
+### 升级前备份（推荐）
+
+```bash
+cp ~/.openclaw/openclaw.json ~/.openclaw/openclaw.json.bak
+```
+
 ## Architecture: Plugin vs Skill
 
 Previous versions (v0.x) shipped as a **skill** — a markdown file that asked the model to read/write `CURRENT_STATE.md`. This was unreliable because models could ignore the instructions.