port profile and explore pages to useInfiniteLoader

src/routes/(app)/[username]/+page.svelte

@@ -1,11 +1,12 @@
 <script lang="ts">
 	import type { PageData } from './$types'
+	import { onDestroy } from 'svelte'
 	import { createInfiniteQuery } from '@tanstack/svelte-query'
 	import ExploreGrid from '$lib/components/explore/ExploreGrid.svelte'
 	import ProfileHeader from '$lib/components/profile/ProfileHeader.svelte'
 	import { userQueries } from '$lib/api/queries/user.queries'
 	import { crewStore } from '$lib/stores/crew.store.svelte'
-	import { IsInViewport } from 'runed'
+	import { useInfiniteLoader } from '$lib/stores/loaderState.svelte'
 	import Icon from '$lib/components/Icon.svelte'
 	import Button from '$lib/components/ui/Button.svelte'
 	import PageMeta from '$lib/components/PageMeta.svelte'
@@ -18,6 +19,8 @@
 	const viewerCrewRole = $derived(crewStore.membership?.role ?? null)
 	const viewerCrewId = $derived(crewStore.crew?.id ?? null)
 
+	let sentinelEl = $state<HTMLElement>()
+
 	const partiesQuery = createInfiniteQuery(() => ({
 		...userQueries.parties(data.user?.username ?? ''),
 		enabled: !!data.user?.username,
@@ -38,30 +41,18 @@
 		initialDataUpdatedAt: 0
 	}))
 
+	// State-gated infinite scroll
+	const loader = useInfiniteLoader(() => partiesQuery, () => sentinelEl, { rootMargin: '300px' })
+
+	// Cleanup on destroy
+	onDestroy(() => loader.destroy())
+
 	const items = $derived(() => {
 		if (!partiesQuery.data?.pages) return data.items || []
 		return partiesQuery.data.pages.flatMap((page) => page.results ?? [])
 	})
 
 	const isEmpty = $derived(!partiesQuery.isLoading && items().length === 0)
-	const showSentinel = $derived(partiesQuery.hasNextPage && !partiesQuery.isFetchingNextPage)
-
-	let sentinelEl = $state<HTMLElement>()
-
-	const inViewport = new IsInViewport(() => sentinelEl, {
-		rootMargin: '300px'
-	})
-
-	$effect(() => {
-		if (
-			inViewport.current &&
-			partiesQuery.hasNextPage &&
-			!partiesQuery.isFetchingNextPage &&
-			!partiesQuery.isLoading
-		) {
-			partiesQuery.fetchNextPage()
-		}
-	})
 </script>
 
 <PageMeta
@@ -104,9 +95,11 @@
 		<div class="profile-grid">
 			<ExploreGrid items={items()} />
 
-			{#if showSentinel}
+			<div
-				<div class="load-more-sentinel" bind:this={sentinelEl}></div>
+				class="load-more-sentinel"
-			{/if}
+				bind:this={sentinelEl}
+				class:hidden={!partiesQuery.hasNextPage}
+			></div>
 
 			{#if partiesQuery.isFetchingNextPage}
 				<div class="loading-more">
@@ -169,6 +162,10 @@
 	.load-more-sentinel {
 		height: 1px;
 		margin-top: $unit;
+
+		&.hidden {
+			display: none;
+		}
 	}
 
 	.loading-more {

src/routes/(app)/[username]/favorites/+page.svelte

@@ -2,42 +2,33 @@
 
 <script lang="ts">
 	import type { PageData } from './$types'
+	import { onDestroy } from 'svelte'
 	import { createInfiniteQuery } from '@tanstack/svelte-query'
 	import ExploreGrid from '$lib/components/explore/ExploreGrid.svelte'
 	import ProfileHeader from '$lib/components/profile/ProfileHeader.svelte'
 	import { userQueries } from '$lib/api/queries/user.queries'
-	import { IsInViewport } from 'runed'
+	import { useInfiniteLoader } from '$lib/stores/loaderState.svelte'
 	import Icon from '$lib/components/Icon.svelte'
 	import Button from '$lib/components/ui/Button.svelte'
 
 	const { data }: { data: PageData } = $props()
 
+	let sentinelEl = $state<HTMLElement>()
+
 	const favoritesQuery = createInfiniteQuery(() => userQueries.favorites())
 
+	// State-gated infinite scroll
+	const loader = useInfiniteLoader(() => favoritesQuery, () => sentinelEl, { rootMargin: '300px' })
+
+	// Cleanup on destroy
+	onDestroy(() => loader.destroy())
+
 	const items = $derived(() => {
 		if (!favoritesQuery.data?.pages) return []
 		return favoritesQuery.data.pages.flatMap((page) => page.items ?? [])
 	})
 
 	const isEmpty = $derived(!favoritesQuery.isLoading && items().length === 0)
-	const showSentinel = $derived(favoritesQuery.hasNextPage && !favoritesQuery.isFetchingNextPage)
-
-	let sentinelEl = $state<HTMLElement>()
-
-	const inViewport = new IsInViewport(() => sentinelEl, {
-		rootMargin: '300px'
-	})
-
-	$effect(() => {
-		if (
-			inViewport.current &&
-			favoritesQuery.hasNextPage &&
-			!favoritesQuery.isFetchingNextPage &&
-			!favoritesQuery.isLoading
-		) {
-			favoritesQuery.fetchNextPage()
-		}
-	})
 </script>
 
 <svelte:head>
@@ -77,9 +68,11 @@
 		<div class="profile-grid">
 			<ExploreGrid items={items()} />
 
-			{#if showSentinel}
+			<div
-				<div class="load-more-sentinel" bind:this={sentinelEl}></div>
+				class="load-more-sentinel"
-			{/if}
+				bind:this={sentinelEl}
+				class:hidden={!favoritesQuery.hasNextPage}
+			></div>
 
 			{#if favoritesQuery.isFetchingNextPage}
 				<div class="loading-more">
@@ -142,6 +135,10 @@
 	.load-more-sentinel {
 		height: 1px;
 		margin-top: $unit;
+
+		&.hidden {
+			display: none;
+		}
 	}
 
 	.loading-more {

src/routes/(app)/teams/explore/+page.svelte

@@ -1,9 +1,10 @@
 <script lang="ts">
   import type { PageData } from './$types'
+  import { onDestroy } from 'svelte'
   import { createInfiniteQuery } from '@tanstack/svelte-query'
   import ExploreGrid from '$lib/components/explore/ExploreGrid.svelte'
   import { partyQueries } from '$lib/api/queries/party.queries'
-  import { IsInViewport } from 'runed'
+  import { useInfiniteLoader } from '$lib/stores/loaderState.svelte'
   import Icon from '$lib/components/Icon.svelte'
   import Button from '$lib/components/ui/Button.svelte'
   import PageMeta from '$lib/components/PageMeta.svelte'
@@ -11,6 +12,8 @@
 
   const { data } = $props() as { data: PageData }
 
+  let sentinelEl = $state<HTMLElement>()
+
   const partiesQuery = createInfiniteQuery(() => ({
     ...partyQueries.list(),
     initialData: data.items
@@ -30,29 +33,17 @@
     initialDataUpdatedAt: 0
   }))
 
+  // State-gated infinite scroll
+  const loader = useInfiniteLoader(() => partiesQuery, () => sentinelEl, { rootMargin: '300px' })
+
+  // Cleanup on destroy
+  onDestroy(() => loader.destroy())
+
   const items = $derived(
     partiesQuery.data?.pages.flatMap((page) => page.results) ?? data.items ?? []
   )
 
   const isEmpty = $derived(!partiesQuery.isLoading && items.length === 0)
-  const showSentinel = $derived(partiesQuery.hasNextPage && !partiesQuery.isFetchingNextPage)
-
-  let sentinelEl = $state<HTMLElement>()
-
-  const inViewport = new IsInViewport(() => sentinelEl, {
-    rootMargin: '300px'
-  })
-
-  $effect(() => {
-    if (
-      inViewport.current &&
-      partiesQuery.hasNextPage &&
-      !partiesQuery.isFetchingNextPage &&
-      !partiesQuery.isLoading
-    ) {
-      partiesQuery.fetchNextPage()
-    }
-  })
 </script>
 
 <PageMeta title={m.page_title_teams()} description={m.page_desc_teams()} />
@@ -81,9 +72,11 @@
     <div class="explore-grid">
       <ExploreGrid items={items} />
 
-      {#if showSentinel}
+      <div
-        <div class="load-more-sentinel" bind:this={sentinelEl}></div>
+        class="load-more-sentinel"
-      {/if}
+        bind:this={sentinelEl}
+        class:hidden={!partiesQuery.hasNextPage}
+      ></div>
 
       {#if partiesQuery.isFetchingNextPage}
         <div class="loading-more">
@@ -150,6 +143,10 @@
   .load-more-sentinel {
     height: 1px;
     margin-top: $unit;
+
+    &.hidden {
+      display: none;
+    }
   }
 
   .loading-more {