Add OTel Integration tracking

[bwoebi]

• Fires app-integration-changed events whenever a CachedInstrumentation object is constructed. (this generally happens once in constructors of well-behaving OTel integrations.
• Adds a component tag to spans created from a tracer created by the CachedInstrumentation object.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 60.86957% with 9 lines in your changes missing coverage. Please review.

Project coverage is 73.02%. Comparing base (368a541) to head (b179d88).
Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
...rc/DDTrace/OpenTelemetry/CachedInstrumentation.php	63.63%	8 Missing ⚠️
src/bridge/_files_opentelemetry.php	0.00%	1 Missing ⚠️

❌ Your patch status has failed because the patch coverage (60.86%) is below the target coverage (90.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #3084      +/-   ##
============================================
- Coverage     73.04%   73.02%   -0.02%     
  Complexity     2792     2792              
============================================
  Files           139      140       +1     
  Lines         15284    15307      +23     
  Branches       1047     1047              
============================================
+ Hits          11164    11178      +14     
- Misses         3567     3576       +9     
  Partials        553      553              

Flag	Coverage Δ
appsec-extension	68.28% <ø> (ø)
tracer-php	74.83% <60.86%> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/bridge/_files_opentelemetry.php	0.00% <0.00%> (ø)
...rc/DDTrace/OpenTelemetry/CachedInstrumentation.php	63.63% <63.63%> (ø)

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[pr-commenter]

Benchmarks [ tracer ]

Benchmark execution time: 2025-02-20 23:35:54

Comparing candidate commit b179d88 in PR branch bob/otel-integration-track with baseline commit 368a541 in branch master.

Found 2 performance improvements and 1 performance regressions! Performance is the same for 175 metrics, 0 unstable metrics.

scenario:LogsInjectionBench/benchLogsInfoInjection-opcache

• 🟩 execution_time [-520.782ns; -224.418ns] or [-5.294%; -2.281%]

scenario:PDOBench/benchPDOBaseline

• 🟥 execution_time [+16.605µs; +17.703µs] or [+9.138%; +9.743%]

scenario:PDOBench/benchPDOBaseline-opcache

• 🟩 execution_time [-17.687µs; -12.216µs] or [-8.878%; -6.132%]

[PROFeNoM]

LGTM 👍 Added one comment, but it's more a nit than anything else; doesn't really matter.

[PROFeNoM]

Perhaps this should be removed?