Feat: navigation clavier + routing ancre sur Play

- ArrowRight/Left : navigue entre les jeux
  aux limites (premier/dernier), passe à la slide prev/next
- Ancres URL (#slug) : set à chaque changement de jeu,
  restaurées au chargement, effacées quand on quitte la slide

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/views/Play.svelte

@@ -1,34 +1,57 @@
 <script>
   import { onMount } from 'svelte'
   import { slides } from '@state/slides.svelte'
+  import { slideTo } from '@router'
   import ResponsivePicture from '@components/ui/ResponsivePicture.svelte'
 
   let { data } = $props()
 
   // --- Derived ---
-  const isActive = $derived(slides.active?.id === 'jouer')
-  const games    = $derived(data?.games ?? [])
+  const isActive      = $derived(slides.active?.id === 'jouer')
+  const games         = $derived(data?.games ?? [])
+  const prevSlidePath = $derived(slides.all[slides.activeIndex - 1]?.path ?? null)
+  const nextSlidePath = $derived(slides.all[slides.activeIndex + 1]?.path ?? null)
 
   // --- State ---
-  let currentIndex   = $state(0)   // index actif (carousel + bg)
-  let displayedIndex = $state(0)   // index du contenu affiché
+  let currentIndex   = $state(0)
+  let displayedIndex = $state(0)
   let phase          = $state('idle') // 'idle' | 'exiting' | 'entering'
-  let slideDir       = $state(1)      // 1 = click droite (exit gauche), -1 = click gauche (exit droite)
+  let slideDir       = $state(1)      // 1 = exit gauche, -1 = exit droite
 
   // Bg crossfade
-  let prevBgColor    = $state(null)
-  let bgFading       = $state(false)
+  let prevBgColor = $state(null)
+  let bgFading    = $state(false)
 
   const displayedGame = $derived(games[displayedIndex] ?? null)
 
+  // Capture du hash synchrone avant que tout effect puisse le modifier
+  const initialHash = window.location.hash.slice(1)
+
   let t1 = null
   let t2 = null
   let t3 = null
 
+  // --- Ancres ---
+  function setAnchor(index) {
+    const slug = games[index]?.slug
+    if (!slug) return
+    history.replaceState(null, '', '#' + slug)
+  }
+
+  function clearAnchor() {
+    history.replaceState(null, '', window.location.pathname + window.location.search)
+  }
+
+  // Restauration depuis l'ancre URL — une seule fois quand games est prêt
+  $effect(() => {
+    if (games.length === 0 || !initialHash) return
+    const idx = games.findIndex(g => g.slug === initialHash)
+    if (idx > 0) currentIndex = idx
+  })
+
   function selectGame(i) {
     if (i === currentIndex || phase !== 'idle' || !games.length) return
 
-    // slideDir = 1 → clic à droite → content sort par la gauche, entre par la droite
     slideDir = i > currentIndex ? 1 : -1
     phase    = 'exiting'
 
@@ -36,22 +59,39 @@
     clearTimeout(t2)
     clearTimeout(t3)
 
-    // Phase 2 (300ms) : swap contenu + carousel + bg simultanés
     t1 = setTimeout(() => {
       prevBgColor    = displayedGame?.backgroundColor ?? null
       displayedIndex = i
       currentIndex   = i
       phase          = 'entering'
       bgFading       = true
+      setAnchor(i)
 
-      // Fin du bg fade
       t3 = setTimeout(() => { bgFading = false }, 500)
-
-      // Fin de l'entrée
       t2 = setTimeout(() => { phase = 'idle' }, 350)
     }, 300)
   }
 
+  // --- Clavier ---
+  function onKeyDown(e) {
+    if (!isActive) return
+    if (e.key === 'ArrowRight') {
+      e.preventDefault()
+      if (currentIndex < games.length - 1) {
+        selectGame(currentIndex + 1)
+      } else if (nextSlidePath) {
+        slideTo(nextSlidePath)
+      }
+    } else if (e.key === 'ArrowLeft') {
+      e.preventDefault()
+      if (currentIndex > 0) {
+        selectGame(currentIndex - 1)
+      } else if (prevSlidePath) {
+        slideTo(prevSlidePath)
+      }
+    }
+  }
+
   // Réinitialisation quand on quitte la slide
   $effect(() => {
     if (!isActive) {
@@ -62,13 +102,18 @@
       displayedIndex = 0
       phase          = 'idle'
       bgFading       = false
+      clearAnchor()
     }
   })
 
-  onMount(() => () => {
-    clearTimeout(t1)
-    clearTimeout(t2)
-    clearTimeout(t3)
+  onMount(() => {
+    window.addEventListener('keydown', onKeyDown)
+    return () => {
+      window.removeEventListener('keydown', onKeyDown)
+      clearTimeout(t1)
+      clearTimeout(t2)
+      clearTimeout(t3)
+    }
   })
 </script>