<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** #43667
# Summary
Renames the unreleased GitOps field `setup_experience_platforms` to
singular `setup_experience_platform`, accepting a comma-separated string
of `darwin`/`linux` (rejecting the `macos` alias) to match the
query/policy/label `platform` convention.
# Checklist for submitter
- [ ] Input data is properly validated, `SELECT *` is avoided, SQL
injection is prevented (using placeholders for values in statements), JS
inline code is prevented especially for url redirects, and untrusted
data interpolated into shell scripts/commands is validated against shell
metacharacters.
## Testing
- [ ] Added/updated automated tests
- [ ] QA'd all new/changed functionality manually
## New Fleet configuration settings
- [ ] Verified that the setting is exported via `fleetctl
generate-gitops`
- [ ] Verified the setting is documented in a separate PR to [the GitOps
documentation](https://github.com/fleetdm/fleet/blob/main/docs/Configuration/yaml-files.md#L485)
- [ ] Verified that the setting is cleared on the server if it is not
supplied in a YAML file (or that it is documented as being optional)
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Improvements**
* Updated software setup-experience platform configuration to use a
single comma-separated `setup_experience_platform` value.
* Platform values are normalized for casing and whitespace,
deduplicated, and validated against supported platforms.
* macOS setup selections now use the canonical `darwin` value; the
`macos` alias is rejected.
* GitOps-generated configurations now use the updated field name and
platform format.
* **Bug Fixes**
* Improved validation messages for invalid setup-experience platform
values.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Carlo
5e2b76a3ad