[feat] add distributed tracing using OTEL

[shanduur]

What this PR does / why we need it:
This PR introduces distributed tracing to the CAPL manager using OpenTelemetry (OTEL) Autoexport. It enhances observability by providing detailed insights into the internal workings of the CAPL manager, which helps in performance monitoring, debugging, and integration with observability backends like Zipkin and Jaeger. Additionally, a new chapter on tracing has been added to the documentation to guide users on configuring and using this feature.

Special notes for your reviewer:
Please review the new tracing chapter in the documentation for accuracy and completeness. Ensure that the instructions for installing the OpenTelemetry Collector and setting up environment variables are clear and easy to follow.

TODOs:

• squashed commits
• includes documentation
• adds unit tests
• adds or updates e2e tests

[codecov]

Codecov Report

Attention: Patch coverage is 53.21101% with 51 lines in your changes missing coverage. Please review.

Project coverage is 66.55%. Comparing base (5e2d469) to head (58ce51e).

Files	Patch %	Lines
cmd/main.go	36.48%	44 Missing and 3 partials ⚠️
observability/tracing/tracing.go	71.42%	3 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #372      +/-   ##
==========================================
+ Coverage   66.25%   66.55%   +0.30%     
==========================================
  Files          40       41       +1     
  Lines        2332     2407      +75     
==========================================
+ Hits         1545     1602      +57     
- Misses        714      728      +14     
- Partials       73       77       +4     

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