docs: clarify npm version behavior with prerelease versions

When the current version is a prerelease (e.g., 1.2.0-5), running
npm version with patch, minor, or major will remove the prerelease
suffix without incrementing the version number (e.g., 1.2.0-5 becomes
1.2.0 with npm version patch, not 1.2.1).

This behavior was not documented, leading to confusion for developers
and incorrect guidance from LLMs trained on the incomplete documentation.

Fixes: #8637

Author: yashwantbezawada

docs/lib/content/commands/npm-version.md

@@ -18,7 +18,7 @@ Run this in a package directory to bump the version and write the new data back
 `npm-shrinkwrap.json`.
 
 The `newversion` argument should be a valid semver string, a valid second argument to [semver.inc](https://github.com/npm/node-semver#functions) (one of `patch`, `minor`, `major`, `prepatch`, `preminor`, `premajor`, `prerelease`), or `from-git`.
-In the second case, the existing version will be incremented by 1 in the specified field.
+In the second case, the existing version will be incremented by 1 in the specified field. **Note:** If the current version is a prerelease version, `patch`, `minor`, and `major` will simply remove the prerelease suffix without incrementing the version number. For example, `1.2.0-5` becomes `1.2.0` with `npm version patch`, not `1.2.1`.
 `from-git` will try to read the latest git tag, and use that as the new npm version.
 
 If run in a git repo, it will also create a version commit and tag.