fix: use spendable coins not balance, avoid nil slice, sim, budget

[dongsam]

Description

closes: #251

Tasks

• fix: use spendable coins not balance
• fix: bech32 as byte, spec ordering
• fix: avoid nil slice on farming module
• bump budget to v1.1.0, fix simulation

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[dongsam]

Great work! LGTM other than the following question.

In keeper/genesis.go, i see GetAllBalances is used in both InitGenesis and ExportGenesis. Am I understanding correctly that the function must be used to include all the account balances?

@kogisin That's right, unlike using SpendableCoins elsewhere accompanied by Send, Genesis uses GetAllBalances because it is for verification, not send, and the vesting locked amount of export and init varies depending on the block time, which can break the invariant of SpendableCoins.