feat: Show Wei validation only when sending Ether. Other tokens use validation if input more than token dps

Fixes error `Uncaught Error: lt() number type has more than 15 significant` that occurs when for example the users
balance is 0.999368704999999998, the tx fee is 0.000063 (i.e. 3Gwei * 21000)

feat: Show Wei validation only when sending Ether. Other tokens use validation if input more than token dps