theme: Fix Alpine broken by Turbo v8.0.21

Turbo v8.0.21 changed same-page anchor handling to let the browser
manage them directly, but this causes turbo:before-cache to fire without
a corresponding turbo:render event. This stopped Alpine's mutation
observer without restarting it, breaking all Alpine interactivity (TOC,
search, navbar).

Remove Alpine.stopObservingMutations() from turbo:before-cache since it
now fires on same-page anchor clicks.

Closes gohugoio#3361

Author: jmooring

assets/js/helpers/bridgeTurboAndAlpine.js

@@ -30,9 +30,6 @@ export function bridgeTurboAndAlpine(Alpine) {
 
 	// Cleanup Alpine state on navigation.
 	document.addEventListener('turbo:before-cache', () => {
-		// This will be restarted in turbo:render.
-		Alpine.stopObservingMutations();
-
 		document.body.querySelectorAll('[data-turbo-permanent]').forEach((el) => {
 			if (!el.hasAttribute('x-ignore')) {
 				el.setAttribute('x-ignore', true);