[Refactor] AccountsViewModel: use by delegation for mutable states

[shamim-emon]

Please confirm the following

• I checked the current issues for duplicate issues.

What would you like to improve?

Rework val x = mutableStateOf() and x.value to x by mutableStateOf() and x.

Because...
It's more convenient to use and the code becomes simpler to read.

Description
No response

Success Criteria
No functional changes
The app works as expected

[ivywallet]

Thank you @shamim-emon for raising Issue #3520! 🚀
What's next? Read our Contribution Guidelines 📚.

Tagging @ILIYANGERMANOV for review & approval 👀

[prathmeshkc]

I'm on it

[ivywallet]

⚠️ Hey @prathmeshkc, this issue is not approved, yet.
@ILIYANGERMANOV must approve it first.

Also, make sure to read our Contribution Guidelines.

[shamim-emon]

I'm on it

[ivywallet]

Thank you for your interest @shamim-emon! 🎉
Issue #3520 is assigned to you. You can work on it! ✅

If you don't want to work on it now, please un-assign yourself so other contributors can take it.

Also, make sure to read our Contribution Guidelines.