refactor: streamline post sync, fix image gallery, and clean up chat screen

- **Post sync optimization**: Clear store immediately when params change to prevent flashing old posts; replace instead of merge on refresh
- **ImageGallery fix**: Use idempotent download option, migrate to Asset.create() API, fix Android file path requirement, ensure proper cleanup
- **UserProfileScreen**: Add ImageGallery for post image viewing with consistent implementation
- **SearchScreen**: Add entrance animation and empty state
- **ChatScreen**: Remove unused state variables (lastSeq, firstSeq, isProgrammaticScrollRef) and dead imports

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "with_you",
-  "version": "1.0.0",
+  "version": "1.0.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "with_you",
-      "version": "1.0.0",
+      "version": "1.0.1",
       "dependencies": {
         "@expo/ui": "~56.0.17",
         "@expo/vector-icons": "^15.1.1",