<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** Resolves#47492 and Resolves#46982
- Fixed panic when uploading bad profile
- Added validation for SCEP challenge to exclude underscore (and other
non-printable characters).
# Checklist for submitter
If some of the following don't apply, delete the relevant line.
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.
- [x] 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
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Bug Fixes**
* Prevented a server panic during Windows configuration profile
validation when SCEP and non-SCEP elements are mixed; such profiles are
now rejected with a clear validation error.
* **New Features**
* Enforced Windows-compatible printable characters for Custom SCEP proxy
challenge values; rejects disallowed characters while preserving legacy
values unless changed.
* **UI / Validation**
* Improved form validation feedback for the Custom SCEP challenge field,
showing errors and disabling submit for invalid input while allowing
masked/unchanged values.
* **Tests**
* Added regression and unit tests covering profile validation and
challenge character validation.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Victor Lyuboslavsky
4fdd4bd3b4