[CL Incentives] Allow early withdrawals for frozen positions

[AlpinYukseloglu]

Background

We've internally agreed that hard-enforcing freezes by not allowing early withdrawals at all might be a little too constraining for users, even though freezing is a major relaxation compared to bonding already.

The simplest and cleanest approach (both as a mechanism and from an implementation standpoint) seems to be to simply deposit any accrued rewards from an early exit back into its respective accumulator. This effectively causes the early withdrawer to forfeit their earnings such that they are redistributed pro-rata to the existing LPs.

Suggested Design

• Remove the following check:
  

  osmosis/x/concentrated-liquidity/lp.go

  Lines 127 to 130 in ccc07c3

  	// Check if position is still frozen
  	if position.FrozenUntil.After(ctx.BlockTime()) {
  	return sdk.Int{}, sdk.Int{}, types.PositionStillFrozenError{FrozenUntil: position.FrozenUntil}
  	}

• Replace it with (roughly) the following logic:

preparePositionAccumulator(...)
rewards := ClaimRewards(...)
AddToAccumulator(rewards / liquidity)

Acceptance Criteria

• All new and existing tests pass