fix: forms on pages TYPO3 13 renders itself can be submitted

The .form-island wrapper existed only in the form page type (/form), so
on pages TYPO3 13 renders completely (e.g. the EP ambassador page) the
form's hx-target="closest .form-island" found nothing and submitting did
nothing. The island with its loading overlay now comes from the form
plugin's template (Render.html), on full pages and in /form alike; the
page type renders just the plugin again.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

packages/ep_theme/Configuration/TypoScript/Extensions/Form.typoscript

@@ -4,6 +4,8 @@
 
 plugin.tx_form.view {
     templateRootPaths.10 = EXT:ep_theme/Resources/Private/Templates/Form/
+    # Spinner.html for Render.html
+    partialRootPaths.10 = EXT:ep_theme/Resources/Private/Partials/Form/
 }
 
 plugin.tx_form.settings.yamlConfigurations {