TW-1806: add custom mimeType for fileInfo

lib/src/utils/models/file_info.dart

@@ -9,22 +9,23 @@ class FileInfo with EquatableMixin {
   final String filePath;
   final int fileSize;
   final Stream<List<int>>? readStream;
+  final String? customMimeType;
 
   FileInfo(
     this.fileName,
     this.filePath,
     this.fileSize, {
     this.readStream,
+    this.customMimeType,
   });
 
   factory FileInfo.empty() {
     return FileInfo('', '', 0);
   }
 
   String get mimeType =>
-      lookupMimeType(filePath) ??
-      lookupMimeType(fileName) ??
-      'application/octet-stream';
+      customMimeType ?? lookupMimeType(filePath) ?? lookupMimeType(fileName) ?? 'application/octet-stream';
+
 
   Map<String, dynamic> get metadata => ({
         'mimetype': mimeType,
@@ -39,6 +40,7 @@ class FileInfo with EquatableMixin {
         file.size,
         width: file.info['w'],
         height: file.info['h'],
+        customMimeType: file.mimeType,
       );
     } else if (file.msgType == MessageTypes.Video) {
       return VideoFileInfo(
@@ -51,9 +53,10 @@ class FileInfo with EquatableMixin {
         duration: file.info['duration'] != null && file.info['duration'] is int
             ? Duration(milliseconds: file.info['duration'])
             : null,
+        customMimeType: file.mimeType,
       );
     }
-    return FileInfo(file.name, file.filePath ?? '', file.size);
+    return FileInfo(file.name, file.filePath ?? '', file.size, customMimeType: file.mimeType,);
   }
 
   @override

lib/src/utils/models/image_file_info.dart

@@ -6,6 +6,7 @@ class ImageFileInfo extends FileInfo {
     super.filePath,
     super.fileSize, {
       super.readStream,
+      super.customMimeType,
       this.width,
       this.height,
     }

lib/src/utils/models/video_file_info.dart

@@ -16,6 +16,7 @@ class VideoFileInfo extends FileInfo {
     super.filePath,
     super.fileSize, {
     super.readStream,
+    super.customMimeType,
     required this.imagePlaceholderBytes,
     this.width,
     this.height,