Update spec: add cli to update --item options

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

Author: ptrthomas

docs/spec.md

@@ -316,7 +316,7 @@ Check for updates and download new versions. Interactive by default.
 
 **Flags:**
 * `--all` — Update all components non-interactively
-* `--item <name>` — Update specific item: jar, jre
+* `--item <name>` — Update specific item: jar, jre, cli
 
 ---