api, metrics: add additional RTSP statistics (#3312)

[aler9]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 100 lines in your changes missing coverage. Please review.

Project coverage is 55.69%. Comparing base (3233e48) to head (78890ae).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/metrics/metrics.go	0.00%	82 Missing ⚠️
internal/stream/stream.go	0.00%	8 Missing ⚠️
internal/servers/rtsp/conn.go	0.00%	6 Missing ⚠️
internal/servers/rtsp/session.go	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4073      +/-   ##
==========================================
- Coverage   55.96%   55.69%   -0.27%     
==========================================
  Files         193      193              
  Lines       19689    19782      +93     
==========================================
  Hits        11018    11018              
- Misses       7827     7920      +93     
  Partials      844      844              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[github-actions]

This issue is mentioned in release v1.11.0 🚀
Check out the entire changelog by clicking here