Enroll page media screen max width updated (#43666)

<!-- Add the related story/sub-task/bug number, like Resolves #123, or
remove if NA -->
**Related issue:** Resolves #41568

# 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.

## Testing

- [x] QA'd all new/changed functionality manually
<img width="751" height="239" alt="Localhost pixel 9pro xl emulation"
src="https://github.com/user-attachments/assets/2ad2d07a-aca8-4c4f-bbe2-0700736a51a4"
/>


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Style**
* Adjusted the enrollment page responsive layout so the enroll button
renders at full width on larger-resolution mobile and medium screens.
* Increased spacing between device instructions and the enrollment
action to improve layout clarity.
* Visual-only change — no functional or behavioral modifications to the
enrollment flow.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

changes/41568-enroll-page-enroll-button-update-to-full-width-for-larger-res-mobiles

@@ -0,0 +1 @@
+- Enrolment page enroll button updated to render full screen width for larger resolution mobile devices

frontend/templates/enroll-ota.html

@@ -184,7 +184,7 @@
         text-align: center;
       }
 
-      @media screen and (max-width: 430px) {
+      @media screen and (max-width: 1344px) and (pointer: coarse) {
         .device-instructions-content {
           gap: 24px;
         }