fix: detect Windows skill paths in telemetry

[dmorosanu]

Summary

Fix skill_triggered detection for Codex telemetry containing Windows paths.

Problem

Codex records skill reads inside PowerShell command strings using backslashes, sometimes retained as doubled JSON-escaped separators. The checker only recognized skills/<name>/, so a skill could be loaded correctly while the evaluation incorrectly reported observed=no. Final scoring and early-stop detection also used separate matching paths, allowing their results to diverge.

Change

Use one shared detector for final scoring and early-stop behavior. It accepts POSIX separators, Windows separators, doubled escaped separators, and overlapping repository paths such as skills/skills/<name>/.

Validation

• 127 passed: tests/test_skill_triggered.py and tests/test_early_stop.py
• Ruff lint and formatting passed
• Rechecked the four original troubleshoot trajectories: all report skill_triggered as observed=yes, score 1.0
• Fresh four-test end-to-end run: activation passed in all four scenarios

[github-actions]

Claude finished @dmorosanu's task in 1m 36s —— View job

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