feat: add monitoring for signer agreement state conflict

[fdefelici]

Description

This change implement prometheus monitoring metrics for signer agreement state conflict.
Basically counting the times the current signer is in conflict with the signer set due to: Burn Block Delay, Stacks Block Delay, Miner View.

Futhermore, monitoring about Signer state upgrade (started in this PR #5981) has been completed collecting the Protocol Upgrade state

Applicable issues

• fixes Implement log collection and monitoring scheme #5918

Additional info (benefits, drawbacks, caveats)

About the conflict "Stacks Block Delay", I'm not sure where to collect it. Any guidance would be helpful.

Eventually, we could also:

• extend the state update change metric (SignerAgreementStateChangeReason) to take into account the case where the signer capitulate on the miner viewpoint:
  

  stacks-core/stacks-signer/src/v0/signer_state.rs

  Lines 819 to 830 in 9d4cc3a

  	if current_miner != new_miner {
  	info!("Capitulating local state machine's current miner viewpoint";
  	"current_miner" => ?current_miner,
  	"new_miner" => ?new_miner,
  	);
  	*self = Self::Initialized(SignerStateMachine {
  	burn_block,
  	burn_block_height,
  	current_miner: (&new_miner).into(),
  	active_signer_protocol_version,
  	});
  	}

• add an new metric to measure the latency required by the signer to reach the agreement with the signer set (basically computed at end of the LocalStateMachine::capitulate_viewpoint(..) method, if the signer can just capitulate once per tenure and considering only the case where some state changes exists)

Checklist

• Test coverage for new or modified code paths
• Changelog is updated
• Required documentation changes (e.g., docs/rpc/openapi.yaml and rpc-endpoints.md for v2 endpoints, event-dispatcher.md for new events)
• New clarity functions have corresponding PR in clarity-benchmarking repo
• New integration test(s) added to bitcoin-tests.yml

[codecov]

Codecov Report

Attention: Patch coverage is 80.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 84.15%. Comparing base (aab7784) to head (5af8521).
Report is 14 commits behind head on develop.

Files with missing lines	Patch %	Lines
stacks-signer/src/v0/signer_state.rs	66.66%	3 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #6008      +/-   ##
===========================================
+ Coverage    84.10%   84.15%   +0.05%     
===========================================
  Files          528      523       -5     
  Lines       385675   384561    -1114     
  Branches       323        0     -323     
===========================================
- Hits        324355   323623     -732     
+ Misses       61312    60938     -374     
+ Partials         8        0       -8     

Files with missing lines	Coverage Δ
stacks-signer/src/monitoring/mod.rs	90.90% <100.00%> (+0.66%)	⬆️
stacks-signer/src/monitoring/prometheus.rs	100.00% <ø> (ø)
stacks-signer/src/v0/signer_state.rs	90.84% <66.66%> (-0.39%)	⬇️

... and 48 files with indirect coverage changes

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