Flutter Application - Maintenance

I need a Flutter programmer to make some changes in an existing application *************************************** Flutter skills are absolutely necessary! *************************************** This app is "Twitter Like": A list of user messages with images eventually attached New functionalities needed: 1) Expand image when clicked (Twitter Like) - Show image in "full screen" when user taps 2) Clip image when on list - Show only a fixed limited portion of image when in list 3) Include "video" support with same behaviour as described above and: - Auto play when in list (without sound) - Play/pause with sound when "full screen" - All videos come from a internet link. 4) Include "documents" support with same behaviour as described above and: - Pick document from local mobile - Show icon for the document in message 5) Open "details" of message with options: - Show conversation - Add a new answer - Repost 6) On message list screen add a widget to show date in a prominent way - Month day / Week Day - List Grouped by mounth - Message list widget already exists. It is just a improvement to use in another screen 7) On "new messsage" screen add new functionalities (New message screen already exists): - Post private messages to individuals (We only need an "incremental search" for individuals - Add support to pick video from gallery and from camera - Add support to pick documents locally - There is already support to post URL from internet. Add support to expand URL and show picture/video if URL points to one (twitter like). Including YouTube links! - Add support to paste picture/video from clipboard General guidelines: - All texts must be provided in separated strings. Please do not hardcode them into widgets - All data related to above tasks are cached locally in SQLITE (using sqflite package). Repositories are used to get data from server and store locally. You DO NOT HAVE to implement these repositories (but you have to use them). Repositories will be implemented by our developer. - You DO NOT HAVE to implement server functionalities. All server API will be implemented by our developer. - Screen rotation must behave consistently - You must provide the flutter source files (dart language) and related resource files.