test(ci): make lint-readme-parity bidirectional

[devantler]

🤖 Generated by the Daily AI Assistant

Fixes #204.

What

Makes the lint-readme-parity CI job bidirectional. It already failed when a declared input/output was missing from a README (forward); this adds the reverse direction — every name in a README's ## Inputs / ## Outputs table first column must be a declared input/output in action.yaml.

Why

The forward-only check is blind to the drift a rename/removal leaves behind: dropping or renaming an input in action.yaml keeps the forward check green (nothing newly undocumented) while the README retains a now-phantom row. This repo has done exactly those changes — require-checks → aggregate-job-checks (v3), setup-copilot-skills → setup-agent-skills (v5), Codecov input/secret removal (v5) — so stale rows are a real, recurring risk. This finishes epic #181's goal of a library "mechanically inspectable for correctness, not just by social convention."

How

• New table_names awk helper reads only the table's first column (skips the header and |---| separator rows; strips backticks) — so prose code-spans don't false-positive (the naive whole-section scan does, verified and rejected).
• Forward logic preserved unchanged.

Validation (local, against this branch's tree)

• actionlint 1.7.12 — no new findings (only the two pre-existing code-quality permission-scope warnings, unrelated).
• yamllint 1.38.0 — clean.
• Extracted the exact embedded script and ran it against all 14 actions:
  • clean tree → pass (exit 0);
  • injected a phantom README row → caught ('ghost' is documented in ## Inputs but not declared in …, exit 1);
  • injected an undocumented declared input → caught (forward still works, exit 1);
  • restored → pass.
• The current tree has no reverse drift, so this lands green and only guards future changes.

Opened as a draft per the maintenance contract; promote to signal go.

[github-code-quality]

Code Coverage Overview

Languages: Go, C#

Go / code-coverage/test

The overall coverage remains at 50%, unchanged from the main branch.

C# / code-coverage/dotnet

The overall coverage remains at 100%, unchanged from the main branch.

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_{Updated June 01, 2026 02:20 UTC
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[Copilot]

Pull request overview

Extends the existing lint-readme-parity CI job in .github/workflows/ci.yaml with a reverse direction check: every name appearing in a README's ## Inputs / ## Outputs markdown table first column must correspond to a declared input/output in the action's action.yaml. This catches stale README rows left behind by renames/removals, which the prior forward-only check missed. Per issue #204 / epic #181, this hardens the library so README↔action.yaml parity is mechanically enforced in both directions.

Changes:

• Add section and table_names awk helpers; table_names reads only the markdown table's first column (skipping header and |---| separator rows, stripping backticks) to avoid false positives from prose code spans.
• Refactor the forward check to consume cached declared_in / declared_out lists and add symmetric reverse-direction loops that emit ::error file=$readme::… annotations.
• Update the success message to reflect the bidirectional guarantee.

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