feat: demonstrate an example of metric ingestion

[kotharironak]

Description

This branch is for demo and exploration purpose, and demonstrate the otlp metric format.

[codecov]

Codecov Report

Merging #249 (93edd27) into main (20b2f53) will decrease coverage by 0.17%.
The diff coverage is 17.64%.

@@             Coverage Diff              @@
##               main     #249      +/-   ##
============================================
- Coverage     80.39%   80.22%   -0.18%     
- Complexity     1152     1161       +9     
============================================
  Files           101      102       +1     
  Lines          4459     4511      +52     
  Branches        416      418       +2     
============================================
+ Hits           3585     3619      +34     
- Misses          679      696      +17     
- Partials        195      196       +1     

Flag	Coverage Δ
unit	80.22% <17.64%> (-0.18%)	⬇️

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Impacted Files	Coverage Δ
...va/org/hypertrace/ingester/HypertraceIngester.java	59.72% <17.64%> (-14.83%)	⬇️
.../enrichedspan/constants/EnrichedSpanConstants.java	50.00% <0.00%> (ø)
...richer/enrichment/enrichers/ExitCallsEnricher.java	100.00% <0.00%> (ø)
...cher/enrichment/clients/DefaultClientRegistry.java	0.00% <0.00%> (ø)
...icher/enrichment/enrichers/TraceStatsEnricher.java	92.00% <0.00%> (ø)

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[github-actions]

Unit Test Results

  70 files  +  1    70 suites  +1   57s ⏱️ -12s
378 tests +12  378 ✔️ +12  0 💤 ±0  0 ❌ ±0 

Results for commit 93edd27. ± Comparison against base commit 20b2f53.