feat(performance): migrate FlatList to FlashList and add animations

Replace FlatList with FlashList across all message screens (ChatScreen, MessageListScreen, NotificationsScreen, HomeScreen) for improved list virtualization performance. Use `drawDistance={250}` instead of manual pagination. Simplify React.memo comparisons in MessageBubble and SegmentRenderer by removing function prop checks to prevent unnecessary re-renders.

Add AsyncStorage persistence for lastSystemMessageAt to avoid showing current time on first render. Include enter animations (fade and slide) for CreateGroupScreen and modernize UI styling to flat design.

BREAKING CHANGE: Upgrade @shopify/flash-list from 2.0.2 to ^2.3.1

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "with_you",
-  "version": "0.1.sha",
+  "version": "0.0.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
@@ -14,7 +14,7 @@
         "@react-navigation/material-top-tabs": "^7.4.16",
         "@react-navigation/native": "^7.1.31",
         "@react-navigation/native-stack": "^7.14.2",
-        "@shopify/flash-list": "2.0.2",
+        "@shopify/flash-list": "^2.3.1",
         "@tanstack/react-query": "^5.90.21",
         "axios": "^1.13.6",
         "date-fns": "^4.1.0",
@@ -3664,13 +3664,10 @@
       }
     },
     "node_modules/@shopify/flash-list": {
-      "version": "2.0.2",
-      "resolved": "https://registry.npmmirror.com/@shopify/flash-list/-/flash-list-2.0.2.tgz",
-      "integrity": "sha512-zhlrhA9eiuEzja4wxVvotgXHtqd3qsYbXkQ3rsBfOgbFA9BVeErpDE/yEwtlIviRGEqpuFj/oU5owD6ByaNX+w==",
+      "version": "2.3.1",
+      "resolved": "https://registry.npmmirror.com/@shopify/flash-list/-/flash-list-2.3.1.tgz",
+      "integrity": "sha512-7oktg2NQR7KAODjFoDaWe8/OBzyYbdTE3zQTrUBMxjIbxHTHN7UXRX1hX3DHk8KvtkgQdRfZOV8Gjj2l4fGrXw==",
       "license": "MIT",
-      "dependencies": {
-        "tslib": "2.8.1"
-      },
       "peerDependencies": {
         "@babel/runtime": "*",
         "react": "*",