Avoid infinite loop by tracking previous head

Prevent infinite reactivity loops by storing the previous head value and only invalidating stacks and details when the head actually changes. The change introduces a previousHead state variable and uses untrack to update it and call stackService.invalidateStacksAndDetails() only when head differs from previousHead.

Author: krlvi

apps/desktop/src/routes/[projectId]/+layout.svelte

@@ -206,9 +206,14 @@
 	const head = $derived(headResponse.response);
 
 	// If the head changes, invalidate stacks and details
+	// We need to track the previous head value to avoid infinite loops
+	let previousHead = $state<string | undefined>(undefined);
 	$effect(() => {
-		if (head) {
-			stackService.invalidateStacksAndDetails();
+		if (head && head !== previousHead) {
+			untrack(() => {
+				previousHead = head;
+				stackService.invalidateStacksAndDetails();
+			});
 		}
 	});