## Issue being fixed or feature implemented
same as  #5392, alternative solution

~based on #5402 atm, will rebase later~

## What was done?
pls see individual commits

## How Has This Been Tested?
reorg mainnet around forkpoint with a patched client (to allow low
difficulty), run tests

## Breaking Changes
Another evodb migration is required. Going back to an older version or
migrating after the fork requires reindexing.

## Checklist:
- [x] I have performed a self-review of my own code
- [x] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] I have made corresponding changes to the documentation
- [x] I have assigned this pull request to a milestone _(for repository
code-owners and collaborators only)_

…/deser pubKeyOperator (#5397)

## Issue being fixed or feature implemented
Mobile wallets would have to convert 4k+ pubkeys at the V19 fork point
and it's a pretty hard job for them that can easily take 10-15 seconds
if not more. Also after the HF, if a masternode list is requested from
before the HF, the operator keys come in basic scheme, but the
merkelroot was calculated with legacy. From mobile team work it wasn't
possible to convert all operator keys to legacy and then calculate the
correct merkleroot.

~This PR builds on top of ~#5392~ #5403 (changes that belong to this PR:
26f7e966500bdea4c604f1d16716b40b366fc707 and
4b42dc8fcee3354afd82ce7e3a72ebe1659f5f22) and aims to solve both of
these issues.~

cc @HashEngineering @QuantumExplorer 

## What was done?
Introduce `nVersion` on p2p level for every CSimplifiedMNListEntry. Set
`nVersion` to the same value we have it in CDeterministicMNState i.e.
pubkey serialization would not be via basic scheme only after the V19
fork, it would match the way it’s serialized on-chain/in
CDeterministicMNState for that specific MN.

## How Has This Been Tested?
run tests

## Breaking Changes
NOTE: `testnet` is going to re-fork at v19 forkpoint because
`merkleRootMNList` is not going to match

## Checklist:
- [x] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] I have made corresponding changes to the documentation
- [ ] I have assigned this pull request to a milestone _(for repository
code-owners and collaborators only)_

same as  dashpay#5392, alternative solution

~based on dashpay#5402 atm, will rebase later~

pls see individual commits

reorg mainnet around forkpoint with a patched client (to allow low
difficulty), run tests

Another evodb migration is required. Going back to an older version or
migrating after the fork requires reindexing.

- [x] I have performed a self-review of my own code
- [x] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] I have made corresponding changes to the documentation
- [x] I have assigned this pull request to a milestone _(for repository
code-owners and collaborators only)_

…/deser pubKeyOperator (dashpay#5397)

Mobile wallets would have to convert 4k+ pubkeys at the V19 fork point
and it's a pretty hard job for them that can easily take 10-15 seconds
if not more. Also after the HF, if a masternode list is requested from
before the HF, the operator keys come in basic scheme, but the
merkelroot was calculated with legacy. From mobile team work it wasn't
possible to convert all operator keys to legacy and then calculate the
correct merkleroot.

~This PR builds on top of ~dashpay#5392~ dashpay#5403 (changes that belong to this PR:
26f7e966500bdea4c604f1d16716b40b366fc707 and
4b42dc8fcee3354afd82ce7e3a72ebe1659f5f22) and aims to solve both of
these issues.~

cc @HashEngineering @QuantumExplorer

Introduce `nVersion` on p2p level for every CSimplifiedMNListEntry. Set
`nVersion` to the same value we have it in CDeterministicMNState i.e.
pubkey serialization would not be via basic scheme only after the V19
fork, it would match the way it’s serialized on-chain/in
CDeterministicMNState for that specific MN.

run tests

NOTE: `testnet` is going to re-fork at v19 forkpoint because
`merkleRootMNList` is not going to match

- [x] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] I have made corresponding changes to the documentation
- [ ] I have assigned this pull request to a milestone _(for repository
code-owners and collaborators only)_

…/deser pubKeyOperator (dashpay#5397)

Mobile wallets would have to convert 4k+ pubkeys at the V19 fork point
and it's a pretty hard job for them that can easily take 10-15 seconds
if not more. Also after the HF, if a masternode list is requested from
before the HF, the operator keys come in basic scheme, but the
merkelroot was calculated with legacy. From mobile team work it wasn't
possible to convert all operator keys to legacy and then calculate the
correct merkleroot.

~This PR builds on top of ~dashpay#5392~ dashpay#5403 (changes that belong to this PR:
26f7e966500bdea4c604f1d16716b40b366fc707 and
4b42dc8fcee3354afd82ce7e3a72ebe1659f5f22) and aims to solve both of
these issues.~

cc @HashEngineering @QuantumExplorer

Introduce `nVersion` on p2p level for every CSimplifiedMNListEntry. Set
`nVersion` to the same value we have it in CDeterministicMNState i.e.
pubkey serialization would not be via basic scheme only after the V19
fork, it would match the way it’s serialized on-chain/in
CDeterministicMNState for that specific MN.

run tests

NOTE: `testnet` is going to re-fork at v19 forkpoint because
`merkleRootMNList` is not going to match

- [x] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] I have made corresponding changes to the documentation
- [ ] I have assigned this pull request to a milestone _(for repository
code-owners and collaborators only)_