Unify minting process experience - BalanceInput.vue

[petersopko]

After we added additional checks in #3546, it would be nice if somebody could take a look at the overall way in which we handle minting process, more specifically, how do we check for things such as:

• [ ] insufficient balance
• [ ] invalid characters
• [ ] form validation in general

As an example, I've noticed one difference: On rmrk, insufficient balance means disabled submit button, on bsx insufficient balance means form validation error. iirc, @roiLeo was fan of the second solution, so we could move with that.

Point is to have similar UI/UX, it shouldn't change based on the chain (other than chain specific features)

// original comment:

ok let's merge this since the bsx part seem so to be working (and that's why the issue was created), however ⚠️ we'll need more refactor, currently, the way we handle form validation / minting at rmrk doesn't match bsx at all (button to submit is disabled there in case of insufficient balance).

Originally posted by @petersopko in https://github.com/kodadot/nft-gallery/issues/3546#issuecomment-1209075113

[Jarsen136]

👋

[kodabot]

ASSIGNED - @Jarsen136 🔒 LOCKED -> Thursday, August 11th 2022, 02:07:16 UTC -> 36 hours