Reduce code duplication in vesting_funds.rs using macros

[coderabbitai]

Description

The vesting_funds.rs file contains significant code duplication between V16 and V17 implementations that could be reduced through macro-ization.

Current State

• VestingFundV16LotusJson and VestingFundV17LotusJson structs are nearly identical
• HasLotusJson implementations for VestingFundV16 and VestingFundV17 are duplicated
• VestingFundsV16LotusJson and VestingFundsV17LotusJson structs are nearly identical
• HasLotusJson implementations for VestingFunds types are duplicated

Proposed Solution

Create macros to generate the common code patterns for different actor versions, reducing maintenance burden and potential for inconsistencies.

References

• PR: feat: integrate v17 actors bundle + 2k network tests [skip ci] #6040
• Original comment: feat: integrate v17 actors bundle + 2k network tests [skip ci] #6040 (comment)

Requested by: @LesnyRumcajs