add jurney animation

src/App.svelte

@@ -4,15 +4,32 @@
   import CountryPicker from './lib/auth/CountryPicker.svelte';
   import Layout from './lib/layout/Layout.svelte';
   import WorldMap from './lib/world-map/WorldMap.svelte';
+  import JourneyView from './lib/world-map/JourneyView.svelte';
   import StatsPanel from './lib/world-map/StatsPanel.svelte';
   import TimelineView from './lib/timeline/TimelineView.svelte';
 
   let screen = $state('worldmap');
+  let journeyActive = $state(false);
+  let journeyProgress = $state(null);
 
   function onNavigate(s) {
     screen = s;
   }
 
+  function startJourney() {
+    journeyActive = true;
+    journeyProgress = null;
+  }
+
+  function endJourney() {
+    journeyActive = false;
+    journeyProgress = null;
+  }
+
+  function onJourneyProgress(p) {
+    journeyProgress = p;
+  }
+
   $effect(() => {
     initAuth();
   });
@@ -30,7 +47,14 @@
   <Layout {screen} {onNavigate}>
     {#if screen === 'worldmap'}
       <div class="worldmap-page">
-        <div class="map-area"><WorldMap /></div>
+        <div class="map-area">
+          {#if journeyActive}
+            <JourneyView onclose={endJourney} onprogress={onJourneyProgress} />
+          {:else}
+            <WorldMap />
+            <button class="journey-play-btn" onclick={startJourney}>▶</button>
+          {/if}
+        </div>
         <StatsPanel />
       </div>
     {:else}
@@ -71,5 +95,36 @@
   .map-area {
     flex: 1;
     overflow: hidden;
+    position: relative;
+  }
+
+  .journey-play-btn {
+    position: absolute;
+    bottom: 24px;
+    right: 24px;
+    z-index: 10;
+    width: 44px;
+    height: 44px;
+    border-radius: 50%;
+    border: none;
+    background: #8b5cf6;
+    color: #fff;
+    font-size: 20px;
+    line-height: 1;
+    cursor: pointer;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    box-shadow: 0 2px 12px rgba(139, 92, 246, 0.4);
+    transition: background 0.15s ease, transform 0.1s ease, box-shadow 0.15s ease;
+  }
+
+  .journey-play-btn:hover {
+    background: #7c3aed;
+    box-shadow: 0 4px 18px rgba(139, 92, 246, 0.55);
+  }
+
+  .journey-play-btn:active {
+    transform: scale(0.92);
   }
 </style>