feat: Add kafka metrics

[GGXXLL]

WIP

[codecov]

Codecov Report

Merging #130 (08bea71) into master (f89361d) will increase coverage by 3.04%.
The diff coverage is 99.20%.

@@            Coverage Diff             @@
##           master     #130      +/-   ##
==========================================
+ Coverage   77.12%   80.17%   +3.04%     
==========================================
  Files          84       87       +3     
  Lines        3205     3698     +493     
==========================================
+ Hits         2472     2965     +493     
+ Misses        546      545       -1     
- Partials      187      188       +1     

Impacted Files	Coverage Δ
otgorm/dependency.go	88.13% <ø> (ø)
otredis/provider.go	77.90% <ø> (ø)
otkafka/module.go	92.85% <92.85%> (ø)
otkafka/writer_metrics.go	94.87% <94.87%> (ø)
observability/metrics.go	100.00% <100.00%> (ø)
observability/observability.go	100.00% <100.00%> (ø)
otkafka/dependency.go	89.58% <100.00%> (+1.77%)	⬆️
otkafka/reader_metrics.go	100.00% <100.00%> (ø)
... and 3 more

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