UI Redesign - Mobile - Trusted Senders

[Jainakin]

- What I did
Created a new UI design for the trusted senders screen and a remove trusted sender dialog which closes #222

- How I did it
I created a new screen for the trusted senders screen inside the trusted_senders_screen folder

- How to verify it
Add this code to the welcome screen and you should be able to click the floating action button to view the new screen

floatingActionButton: FloatingActionButton(
    backgroundColor: const Color(0xFFF05E37),
    child: const ImageIcon(
        AssetImage("assets/images/add_icon.png"),
        color: Colors.white,
        size: 16.0,
    ),
    onPressed: () {
        showModalBottomSheet<dynamic>(
            isScrollControlled: true,
            shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(20.0),
            ),
            context: context,
            builder: (BuildContext context) {
                return TrustedSendersScreen();
            },
        );
    },
),

- Description for the changelog
Added Trusted Sender Screen and Dialog

[tinashe404]

@Jainakin Please could you add the code into the PR so that when we run it we see your changes without any amendments. This screen should be visible when we click on Trusted Senders in the menu that appears on the right side of the screen.

[Jainakin]

@Jainakin Please could you add the code into the PR so that when we run it we see your changes without any amendments. This screen should be visible when we click on Trusted Senders in the menu that appears on the right side of the screen.

Ok, please give me some time.
Thank you