feat: ReplaceKey functionality in Registration and Update pages (#1246)

- Handles auto-extensions key check and install of extend license key
with new OS Updates Expiration date

Related to https://github.com/unraid/webgui/pull/2071 but not 100%
dependent on them.

@elibosley, do we want to use the `force` param on the `check()` method
for either of these pages?

Additionally, what do you think about any potential integration with
`UnraidCheck.php` – which is used for the UPC's "Check for Updates"
button and the user configured automatically scheduled update check?

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

## Summary by CodeRabbit

- **New Features**
- Enhanced plugin registration and update processes with an integrated
key validation step that verifies system parameters automatically.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---
- To see the specific tasks where the Asana app for GitHub is being
used, see below:
  - https://app.asana.com/0/0/1209573221367688

plugin/source/dynamix.unraid.net/usr/local/emhttp/plugins/dynamix.my.servers/Registration.page

@@ -14,6 +14,9 @@ Tag="pencil"
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  */
+require_once "$docroot/plugins/dynamix/include/ReplaceKey.php";
+$replaceKey = new ReplaceKey();
+$replaceKey->check();
 ?>
 <unraid-i18n-host>
   <unraid-registration></unraid-registration>

plugin/source/dynamix.unraid.net/usr/local/emhttp/plugins/dynamix.plugin.manager/Update.page

@@ -14,7 +14,10 @@ Tag="upload"
  * all copies or substantial portions of the Software.
  */
 require_once "$docroot/plugins/dynamix.my.servers/include/reboot-details.php";
+require_once "$docroot/plugins/dynamix/include/ReplaceKey.php";
 $rebootDetails = new RebootDetails();
+$replaceKey = new ReplaceKey();
+$replaceKey->check();
 ?>
 <script>
 function cleanUpFlashBackup(zip) {