docs(readme): document allow-git requirement for npm >= 12

README.md

@@ -52,17 +52,22 @@ On Windows it uses junctions for skill directories and degrades gracefully
 (hardlink, then copy) for agent files; on macOS/Linux it uses relative symlinks.
 
 ```bash
-# one-shot, nothing persisted
-npx git+https://gogs.gvoci.com/softword/oh-my-skills.git
+# npm >= 12 blocks git dependencies by default (EALLOWGIT): allow it per invocation
+npm_config_allow_git=all npx git+https://gogs.gvoci.com/softword/oh-my-skills.git
 
-# or install the command globally
-npm install -g git+https://gogs.gvoci.com/softword/oh-my-skills.git
+# or install the command globally (persistent `agent-sync` in PATH)
+npm_config_allow_git=all npm install -g git+https://gogs.gvoci.com/softword/oh-my-skills.git
 agent-sync
 
 # dry-run: report drift without writing anything (exit 1 when out of sync)
 agent-sync --check
 ```
 
+On cmd.exe run `set npm_config_allow_git=all` first; on PowerShell use
+`$env:npm_config_allow_git='all'`. To pick up new commits, reinstall with the same
+`npm install -g` command: the content is embedded in the package, so tool and
+ content update together.
+
 ## Skill catalog
 
 | Skill | What it is for |