Add tooltip hints to form fields, fix navigation overlap bug

- Create Hint component with fixed-position floating tooltip
- Add hints to tracking configs (periodic/scheduled/memory modes,
  favorites, times, album mode, rating), template configs (section
  legends), targets (AI captions, media settings, config selectors),
  and trackers (scan interval)
- Add 21 hint i18n keys in EN and RU
- Fix transition:slide → in:slide on all pages to prevent content
  overlap when navigating away mid-animation
- Merge Asset Display into Event Tracking fieldset; use consistent
  "Max Assets" label with hint in each section

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/routes/template-configs/+page.svelte

@@ -9,6 +9,7 @@
 	import IconPicker from '$lib/components/IconPicker.svelte';
 	import MdiIcon from '$lib/components/MdiIcon.svelte';
 	import ConfirmModal from '$lib/components/ConfirmModal.svelte';
+	import Hint from '$lib/components/Hint.svelte';
 
 	let configs = $state<any[]>([]);
 	let loaded = $state(false);
@@ -129,7 +130,7 @@
 {#if !loaded}<Loading />{:else}
 
 {#if showForm}
-<div transition:slide>
+<div in:slide>
 <Card class="mb-6">
 	{#if error}<div class="bg-[var(--color-error-bg)] text-[var(--color-error-fg)] text-sm rounded-md p-3 mb-4">{error}</div>{/if}
 	<form onsubmit={save} class="space-y-5">
@@ -144,7 +145,7 @@
 
 		{#each templateSlots as group}
 			<fieldset class="border border-[var(--color-border)] rounded-md p-3">
-				<legend class="text-sm font-medium px-1">{t(`templateConfig.${group.group}`)}</legend>
+				<legend class="text-sm font-medium px-1">{t(`templateConfig.${group.group}`)}{#if group.group === 'eventMessages'}<Hint text={t('hints.eventMessages')} />{:else if group.group === 'assetFormatting'}<Hint text={t('hints.assetFormatting')} />{:else if group.group === 'dateLocation'}<Hint text={t('hints.dateLocation')} />{:else if group.group === 'scheduledMessages'}<Hint text={t('hints.scheduledMessages')} />{/if}</legend>
 				<div class="space-y-3 mt-2">
 					{#each group.slots as slot}
 						<div>