Staking models: Stake 1.0 vs 2.0

wallet-cli supports two generations of the TRON staking mechanism. New usage should prefer Stake 2.0.

Stake 1.0 (legacy)

The original model, driven by freezeBalance / unfreezeBalance:

Freezing specifies a frozen_duration, currently only allowed to be 3 days.
After the freezing time expires, funds can be unfrozen; when the unfreezing operation occurs, bandwidth is not cleared.
Resource delegation is expressed through the optional receiverAddress parameter of the same freeze/unfreeze commands.

The current model, driven by freezeBalanceV2 / unfreezeBalanceV2, with resource delegation and an explicit unbonding/withdrawal flow:

freezeBalanceV2 stakes TRX for BANDWIDTH, ENERGY, or TRON_POWER.
delegateResource / unDelegateResource delegate resources to another account (optionally locked for 3 days).
unfreezeBalanceV2 begins unbonding; withdrawExpireUnfreeze withdraws the amount once it has expired; cancelAllUnfreezeV2 cancels pending unfreezes.
Dedicated v2 query commands report delegation state and available/withdrawable amounts.