github-actions-failure-matrix

# GitHub Actions Failure Matrix

Use this skill to turn noisy GitHub Actions run JSON into a matrix-focused failure report.

## What this skill does
- Reads one or more JSON exports from GitHub Actions runs (via `gh run view --json`)
- Detects failure-like matrix jobs (`failure`, `timed_out`, `cancelled`, etc.)
- Extracts matrix axes from common job-name patterns (`name (a, b)`, `name [a, b]`, `name / a / b`)
- Groups repeated failures by workflow + job + matrix axis signature
- Emits ranked triage output in `text` or `json`

## Inputs
Optional:
- `RUN_GLOB` (default: `artifacts/github-actions/*.json`)
- `TOP_N` (default: `20`)
- `OUTPUT_FORMAT` (`text` or `json`, default: `text`)
- `FAIL_ON_FAILURES` (`0` or `1`, default: `0`) — exit non-zero when failure groups exist
- `MIN_OCCURRENCES` (default: `1`) — hide groups below this repeat count
- `WORKFLOW_MATCH` (regex, optional) — include only workflows whose names match
- `WORKFLOW_EXCLUDE` (regex, optional) — drop workflows whose names match
- `BRANCH_MATCH` (regex, optional) — include only runs whose branch names match
- `BRANCH_EXCLUDE` (regex, optional) — drop runs whose branch names match
- `JOB_MATCH` (regex, optional) — include only base job names that match
- `JOB_EXCLUDE` (regex, optional) — drop base job names that match
- `AXIS_MATCH` (regex, optional) — include only parsed matrix-axis strings that match
- `AXIS_EXCLUDE` (regex, optional) — drop parsed matrix-axis strings that match
- `CONCLUSION_MATCH` (regex, optional) — include only specific failure conclusions (`failure`, `timed_out`, `cancelled`, etc.)
- `CONCLUSION_EXCLUDE` (regex, optional) — drop specific failure conclusions
- `FAILED_STEP_MATCH` (regex, optional) — include only jobs whose terminal failed step matches
- `FAILED_STEP_EXCLUDE` (regex, optional) — drop jobs whose terminal failed step matches
- `RUN_ID_MATCH` (regex, optional) — include only runs whose run id matches
- `RUN_ID_EXCLUDE` (regex, optional) — drop runs whose run id matches...