finalized_block property on Subtensor/SyncClient #3068

Is your feature request related to a problem? Please describe.

The subscription approach to getting the latest blocks (bittensor.Subtensor().blocks(finalized=...)) isn't always ideal. There exists a bittensor.Subtensor().block property but no finalized_block analog for these scenarios.

Describe the solution you'd like

A property, bittensor.Subtensor().finalized_block that behaves just like the corresponding .block property.

Describe alternatives you've considered

The generator bittensor.Subtensor().blocks(finalized=True), but this has reduced flexibility versus a single read.

Additional context

No response