[CHANGELOG] Deprecation warnings for privacy, permissioning, PoW, fast sync

[macfarla]

PR description

for more info - https://www.lfdecentralizedtrust.org/blog/sunsetting-tessera-and-simplifying-hyperledger-besu

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[matthew1001]

I think this is fine @macfarla, especially as it's currently just an announce. The one that I feel I could do with a bit more clarity on is the smart contract permissioning. The blog says "These features have existing and novel app-layer solutions" for tessera and smart contract permissioning, which I agree with for tessera, but I'm not as familiar with possible alternatives for smart contract permissioning.

[macfarla]

I think this is fine @macfarla, especially as it's currently just an announce. The one that I feel I could do with a bit more clarity on is the smart contract permissioning. The blog says "These features have existing and novel app-layer solutions" for tessera and smart contract permissioning, which I agree with for tessera, but I'm not as familiar with possible alternatives for smart contract permissioning.

agree there is some work to do to get permissioning plugin-able eg #7835

[diega]

Is it clear how plugin-able the PoW parts are?

[macfarla]

Is it clear how plugin-able the PoW parts are?

some work needs to be done still to make the consensus mechanism plugin-able - @diega is this something you'd be interested to contributing to?

[diega]

@diega is this something you'd be interested to contributing to?

@macfarla, absolutely. Are there some draft sketches on how this should look like at architectural level? also, how something like this should be configured from the user perspective? a new flag? stripping out the consensus section from the genesis file? something more like SPI?