fix(server): canonicalise media paths the same way their callers do - #9575

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• Check

Verify the requires field in your .macroscope/*.md front matter matches the exact check run name as it appears on GitHub. If the step is real but published late — a conditional job, or a workflow queued while a previous run is still cancelling — raise waitsForDiscoveryTimeout (minutes) to give it longer to appear. The cost of a longer window is that a step which never appears at all takes that long to skip.