Update CustomLink styles (#48838)

<!-- Add the related story/sub-task/bug number, like Resolves #123, or
remove if NA -->
**Related issue:** Resolves #35328

# 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] 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**
* Improved link hover and `:focus-visible` underline/outline behavior
for more consistent accessibility across tables, buttons, and modals.
  * Fixed script name hover underline clipping in the run script modal.
* **Style**
* Refreshed `CustomLink` styling with an emphasized variant and improved
underline behavior, plus updated related link/table/button styling for a
unified look.
* Updated “Connect Fleet” info-banner messaging and CTAs for calendar
and conditional access automations; refreshed “No scripts available”
empty state.
* **Tests**
  * Updated modal tests to match revised link text and accessible names.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

frontend/components/AddHostsModal/PlatformWrapper/AndroidPanel/AndroidPanel.tsx

@@ -47,6 +47,7 @@ const AndroidPanel = ({ enrollSecret }: IAndroidPanelProps) => {
         <CustomLink
           url={PATHS.ADMIN_INTEGRATIONS_MDM_ANDROID}
           text="Turn on Android MDM"
+          emphasized
         />{" "}
         to enroll Android hosts.
       </p>