qa-tests: add Claude's skills to improve the analysis of QA test results.

[mriccobene]

No description provided.

[Copilot]

Pull request overview

Adds a new .claude skill (qa-test-results) that documents how to interpret Erigon’s long-running QA GitHub Actions workflows (sync/tip-tracking, snapshot download, clean exit, and RPC integration/performance), with concrete triage steps and per-workflow reference material.

Changes:

• Introduces a qa-test-results Claude skill with a “cheapest signal first” triage flow and key failure-mode explanations.
• Adds reference docs covering workflow families/artifacts, a triage decision tree, and detailed log-reading guides for sync and RPC QA suites.
• Documents the structure/meaning of result-<chain>.json and how to use it to interpret outcomes and measures.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
.claude/skills/qa-test-results/SKILL.md	Main skill guide for reading QA logs/results and interpreting common failure causes.
.claude/skills/qa-test-results/references/workflows.md	Maps qa-* workflows to runner labels, drivers, artifacts, and where verdicts live.
.claude/skills/qa-test-results/references/triage.md	Step-by-step decision tree for diagnosing red QA checks from cheapest signals upward.
.claude/skills/qa-test-results/references/sync-tests.md	Field-by-field explanation of sync/tip-tracking report blocks and metrics.
.claude/skills/qa-test-results/references/rpc-tests.md	Explains RPC integration vs performance log formats and where pass/fail is determined.
.claude/skills/qa-test-results/references/result-json.md	Defines the schema/meaning of result-<chain>.json, outcomes, reasons, and measures.

Comments suppressed due to low confidence (1)

.claude/skills/qa-test-results/SKILL.md:229

• This references a root CLAUDE.md, but there is no CLAUDE.md at the repository root; the test-skip policy lives in AGENTS.md (see the "Test skips" section). As written, the link/filename will send readers to a non-existent file.

  `batch processing with #blocks=N` and `head updated with age=N` are the
  breadcrumbs that explain a sync-time failure.
- **Never propose muting or skipping a QA test** to get a check green; see the
  project's test-skip policy in `CLAUDE.md`.

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[taratorio]

for future, can also add a symlink reference for codex