fix: reject runs on Depot CI with an explicit error

[fargito]

Fail with an explicit error when the runner runs on Depot CI.

Depot CI is a drop-in replacement for GitHub Actions: it sets GITHUB_ACTIONS=true and the usual GITHUB_* variables, so the runner detected its jobs as GitHub Actions ones. Its run ids (e.g. 271476942194171) do not exist on GitHub Actions, so CodSpeed could not process these runs, and users got no feedback on why.

The GitHub Actions provider now bails before any benchmark runs when DEPOT_JOB_URL is set, pointing to support@codspeed.io and Discord to request Depot CI support. DEPOT_JOB_URL is only set on Depot CI, not on Depot's GitHub Actions runners (Depot environment variables), so those keep working.

$ GITHUB_ACTIONS=true DEPOT_JOB_URL=… codspeed run --mode walltime --skip-upload -- echo hi
Error: Depot CI is not supported yet by CodSpeed.
Reach out at support@codspeed.io or on Discord (https://codspeed.io/discord) to request support for it.

Closes COD-3635

[codspeed]

Merging this PR will degrade performance by 13.99%

⚠️ 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.

❌ 1 regressed benchmark
✅ 32 untouched benchmarks
⏩ 4 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	memtrack track tar	8 s	9.3 s	-13.99%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing fix/reject-depot-ci (66db707) with main (7c135cc)}

Footnotes

1. 4 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. ↩