docs: describe the release mirror and v0.9.1

README.md

@@ -1,3 +1,22 @@
 # multica-cli
 
-Multica CLI release mirror. Artifacts are attached to releases.
+Multica CLI 发版镜像仓（public，可匿名读取）。`multica update` 默认从这里取版本：
+
+- release API：`https://igit.me.iweekos.com/api/v1/repos/aionall/multica-cli/releases/latest`
+- 资产：`https://igit.me.iweekos.com/aionall/multica-cli/releases/download/<tag>/<asset>`
+
+源码仓是 `aionall/multi-taisui`；本仓只放 tar.gz / zip 与 `checksums.txt`。
+
+## 已发布
+
+| tag | commit | 说明 |
+| --- | --- | --- |
+| v0.9.1 | `b2e152ffa` | daemon 任务临时目录迁到 `~/.multica/t`（XIA-536，PR #147 + #149） |
+
+## 覆盖区（仅调试用）
+
+```
+MULTICA_RELEASE_API_BASE_URL=https://igit.me.iweekos.com/api/v1
+MULTICA_RELEASE_OWNER=aionall
+MULTICA_RELEASE_REPO=multica-cli
+```