DEVOPS-829 format Timer as summary/histogram type

[rekibnikufesin]

Description

Follow up PR to complete efforts from #881 as it did not produce the desired results. Digging in revealed that the metrics in question are registered as a Timer, not as Summary. Timer metrics are not part of the defined Prometheus metrics types.

This PR updates the Timer metric type to format and display as a Prometheus Summary metric (which I think was the intended behavior all along), consistent with the changes introduced in #881.
No breaking changes, all data previously presented by the metrics endpoint is still there. Formatting has been changed to follow Prometheus-type definitions, resulting in compatibility with the Open Telemetry Collector.

Changes

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)
• Changes only for a subset of nodes

Checklist

• I have added at least 2 reviewer or the whole pos-v1 team
• I have added sufficient documentation in code
• I will be resolving comments - if any - by pushing each fix in a separate commit and linking the commit hash in the comment reply
• Created a task in Jira and informed the team for implementation in Erigon client (if applicable)
• Includes RPC methods changes, and the Notion documentation has been updated

Testing

• I have added unit tests
• I have added tests to CI
• I have tested this code manually on local environment
• I have tested this code manually on remote devnet using express-cli
• I have tested this code manually on mumbai
• I have created new e2e tests into express-cli

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: -0.07 ⚠️

Comparison is base (f96c668) 56.85% compared to head (df14024) 56.79%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #893      +/-   ##
===========================================
- Coverage    56.85%   56.79%   -0.07%     
===========================================
  Files          617      617              
  Lines        73613    73613              
===========================================
- Hits         41854    41809      -45     
- Misses       28222    28255      +33     
- Partials      3537     3549      +12     

Impacted Files	Coverage Δ
params/config.go	29.52% <ø> (ø)
metrics/prometheus/collector.go	100.00% <100.00%> (ø)

... and 24 files with indirect coverage changes

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