fix: gracefully handle process metrics registration failure on unsupported OSes

[EdgeN8v]

Description

This PR addresses the crash issue reported in #14307 where the collector fails to start on unsupported operating systems (e.g., AIX) due to RegisterProcessMetrics returning an error.

Instead of failing the service initialization, this change logs a warning and allows the collector to continue starting, ensuring that core functionality remains available even if process metrics cannot be collected.

Link to Issue

Fixes #14307

Type of change

• Bug fix (non-breaking change which fixes an issue)

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: EdgeN8v / name: EdgeN8v (9f7c331, b74324a)

[codecov]

Codecov Report

❌ Patch coverage is 84.61538% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.81%. Comparing base (0550b08) to head (b74324a).
⚠️ Report is 11 commits behind head on main.

Files with missing lines	Patch %	Lines
service/service.go	84.61%	1 Missing and 1 partial ⚠️

❌ Your patch status has failed because the patch coverage (84.61%) is below the target coverage (95.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #14319      +/-   ##
==========================================
- Coverage   91.82%   91.81%   -0.02%     
==========================================
  Files         677      677              
  Lines       42679    42690      +11     
==========================================
+ Hits        39192    39195       +3     
- Misses       2429     2434       +5     
- Partials     1058     1061       +3     

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[codspeed-hq]

Merging this PR will improve performance by 31.69%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

#### 🎉 Hooray! `codspeed-go` just leveled up to 1.0.0!

A heads-up, this is a breaking change and it might affect your current performance baseline a bit. But here's the exciting part - it's packed with new, cool features and promises improved result stability 🥳!
Curious about what's new? Visit our releases page to delve into all the awesome details about this new version.

⚡ 3 improved benchmarks
✅ 58 untouched benchmarks
⏩ 20 skipped benchmarks¹

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	BenchmarkLogsMarshalJSON	3.8 µs	3 µs	+29.35%
⚡	BenchmarkMetricsMarshalJSON	5.2 µs	3.9 µs	+31.69%
⚡	BenchmarkTracesMarshalJSON	6 µs	4.6 µs	+28.28%

---

_{Comparing EdgeN8v:fix/14307-aix-crash (b74324a) with main (0550b08)}

Footnotes

1. 20 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[axw]

@EdgeN8v please fix CI. It seems the code is not formatted properly - you should be able to fix that by running make fmt.

[EdgeN8v]

@axw Done. I've ran make fmt.

[evan-bradley]

Thank you for working to address this @EdgeN8v.

Since we have a while until the next release, I'd like to see if we can more robustly address this. If someone else would like to get this in and revisit it later, feel free to dismiss my review.

[dmathieu]

Your latest changes removed the warning when the metrics are disabled. We do want that behavior.
Also, it seems to me than @evan-bradley's suggestion was to use build tags to have the allow list (as gopsutil does), not to keep the strings list.

[evan-bradley]

Thanks @EdgeN8v!

[dmathieu]

If you keep making changes to approved PRs, it will never be merged.

[EdgeN8v]

@dmathieu Apologies for the noise. I misunderstood and thought additional updates were still needed even after the PR was marked ready. I’ve reverted back to the approved state and won’t make further changes unless requested.

[otelbot]

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