Add StateMachineUpdateContent::V1 which inculdes a vector of replay_transactions

[jferrant]

Pulled the state machine version upgrade to a sep PR for replay transactions.

[obycode]

LGTM

[kantai]

This LGTM, but I think this should have some more test coverage:

1. The state_machine_update parsing in the integration test should be explicit about which version it expects.
2. If possible, it'd be good to test the protocol version switch over. i.e., pin the protocol version at "0" for 3 out of 5 signers, then assert that all the signers use V0 when submitting state machine updates. Then unpin 2 of the signers so that they're at version "1", and assert that 4 of the signers switch to using V1.

[kantai]

LGTM, just a couple superficial comments

[codecov]

Codecov Report

Attention: Patch coverage is 26.78133% with 298 lines in your changes missing coverage. Please review.

Project coverage is 53.94%. Comparing base (032d33e) to head (dc5982c).
Report is 22 commits behind head on develop.

Files with missing lines	Patch %	Lines
testnet/stacks-node/src/tests/signer/v0.rs	0.61%	161 Missing ⚠️
libsigner/src/v0/messages.rs	21.05%	75 Missing ⚠️
stacks-signer/src/v0/signer_state.rs	60.00%	48 Missing ⚠️
stacks-signer/src/tests/signer_state.rs	10.00%	9 Missing ⚠️
stackslib/src/chainstate/stacks/mod.rs	0.00%	3 Missing ⚠️
stacks-signer/src/v0/tests.rs	80.00%	2 Missing ⚠️

❌ Your project status has failed because the head coverage (53.94%) is below the target coverage (80.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff              @@
##           develop    #6048       +/-   ##
============================================
+ Coverage    36.40%   53.94%   +17.53%     
============================================
  Files            5      538      +533     
  Lines         1269   387714   +386445     
  Branches       323      323               
============================================
+ Hits           462   209149   +208687     
- Misses         799   178557   +177758     
  Partials         8        8               

Files with missing lines	Coverage Δ
stacks-signer/src/v0/signer.rs	76.66% <100.00%> (ø)
stacks-signer/src/v0/tests.rs	87.64% <80.00%> (ø)
stackslib/src/chainstate/stacks/mod.rs	71.66% <0.00%> (ø)
stacks-signer/src/tests/signer_state.rs	28.61% <10.00%> (ø)
stacks-signer/src/v0/signer_state.rs	80.99% <60.00%> (ø)
libsigner/src/v0/messages.rs	54.82% <21.05%> (ø)
testnet/stacks-node/src/tests/signer/v0.rs	29.03% <0.61%> (ø)

... and 526 files with indirect coverage changes

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