Low-cardinality route from path mode

[grcevski]

OBI does only Java route harvesting at the moment, and while we are expanding that support, there may always be the need to derive the OTel compliant route from the URL path. At the moment, the default mode in OBI is the clustering approach, where we detect IDs and gibberish words.

The clustering (gibberish) detection can be easily defeated via Github like URL patterns. For example, none of these paths are gibberish and will produce a high-cardinality derived route:

/open-telemetry/opentelemetry-ebpf-instrumentation/hooks
/open-telemetry/opentelemetry-ebpf-instrumentation/internal/
/open-telemetry/opentelemetry-ebpf-instrumentation/internal/test
/open-telemetry/opentelemetry-ebpf-instrumentation/internal/tools
...

With this PR I'm introducing a second level route collapsing mechanism, which aggregates by service the high cardinality routes using a trie. We have a new config option which is the allowed cardinality per level and once the paths grow beyond the allowed level, the trie node is collapsed into the wildcard.

[codecov]

Codecov Report

❌ Patch coverage is 83.19328% with 20 lines in your changes missing coverage. Please review.
✅ Project coverage is 55.29%. Comparing base (2bfa737) to head (f866218).
⚠️ Report is 8 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/internal/transform/route/clusterurl/trie.go	83.69%	11 Missing and 4 partials ⚠️
pkg/transform/routes.go	76.19%	3 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #882      +/-   ##
==========================================
+ Coverage   55.15%   55.29%   +0.14%     
==========================================
  Files         251      252       +1     
  Lines       21481    21593     +112     
==========================================
+ Hits        11847    11940      +93     
- Misses       8818     8831      +13     
- Partials      816      822       +6     

Flag	Coverage Δ
integration-test	23.21% <11.76%> (-0.08%)	⬇️
integration-test-arm	0.00% <0.00%> (?)
integration-test-vm-${ARCH}-${KERNEL_VERSION}	0.00% <0.00%> (?)
k8s-integration-test	2.74% <0.00%> (-0.02%)	⬇️
oats-test	0.00% <0.00%> (ø)
unittests	46.44% <80.67%> (+0.18%)	⬆️

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