docs: add notes about nightly channel

Author: pi0

README.md

@@ -51,6 +51,30 @@ await storage.getItem("foo:bar"); // or storage.getItem('/foo/bar')
 
 👉 Check out the [the documentation](https://unstorage.unjs.io) for usage information.
 
+## Nightly release channel
+
+You can use the nightly release channel to try the latest changes in the `main` branch via [`unstorage-nightly`](https://www.npmjs.com/package/unstorage-nightly).
+
+If directly using `unstorage` in your project:
+
+```json
+{
+  "devDependencies": {
+    "unstorage": "npm:unstorage-nightly"
+  }
+}
+```
+
+If using `unstorage` via another tool in your project:
+
+```json
+{
+  "resolutions": {
+    "unstorage": "npm:unstorage-nightly"
+  }
+}
+```
+
 ## Contribution
 
 - Clone repository