fix(p2p): fix metrics in p2p package

[vgonkivs]

Overview

Previously some metrics did not work in the p2p package because Otel does not allow registering multiple callbacks per otel.Meter instance. At some point tracked/disconnected/blocked metrics were overwritten by subscription metric callback. Added single metric.Registration in exchange client and created a separate instance for subscriber metrics.

Checklist

• [ ] New and updated code has appropriate documentation
• [ ] New and updated code has new and/or updated testing
• [ ] Required CI checks are passing
• [ ] Visual proof for any user facing features like CLI or documentation updates
• [ ] Linked issues closed with keywords

[codecov-commenter]

Codecov Report

Attention: 17 lines in your changes are missing coverage. Please review.

Comparison is base (28ff21c) 63.60% compared to head (2d1debb) 64.11%. Report is 10 commits behind head on main.

Files	Patch %	Lines
p2p/exchange_metrics.go	0.00%	12 Missing :warning:
p2p/subscriber_metrics.go	0.00%	5 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #144 +/- ## ========================================== + Coverage 63.60% 64.11% +0.50% ========================================== Files 39 39 Lines 3366 3380 +14 ========================================== + Hits 2141 2167 +26 + Misses 1060 1048 -12 Partials 165 165 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.