chore: unpin node-red-standards and declare the coverage configuration

[windkh]

This repo was the reason node-red-standards 0.5.0 grew two new checks.

The reference was frozen at a commit

devDependencies["node-red-standards"] was
https://codeload.github.com/windkh/node-red-standards/tar.gz/1726fe5… — node-red-standards 0.3.0. So this repo stopped receiving the standard three releases ago, while standards-check kept reporting a clean 10/10 against the frozen copy. Nothing could catch that: a Git specifier has no semver major, so the "raise a floor below the baseline" logic never looked at it.

That is also why .github/workflows/node.js.yml here still has no coverage step at all — the workflow that added one never arrived.

Now github:windkh/node-red-standards, which dependabot can move. 0.5.0 treats any other specifier for itself as drift and reports unpin (was frozen at a commit).

The missing c8 block was a hidden 90% gate

There was no c8 block, and c8 --check-coverage with no block falls back to c8's own defaults — 90% lines (branches, functions and statements default to 0). Measured here:

All files | 56.56 % lines | 71.6 % branches | 64 % functions

So the moment the current node.js.yml arrives with its npm run coverage:check step, CI would have gone red on a threshold nobody chose. The thresholds are therefore set explicitly at the measured floor (lines 56, statements 56, branches 71, functions 64), and the reporter now emits lcov so the workflow's coverage artifact contains something readable instead of only c8's raw V8 dump under coverage/tmp/.

node-red-standards 0.5.1 adds an audit check for exactly this: c8.lines must be stated, because omitting it silently means 90%.

Verified locally: lint, format:check, 20 tests, and coverage:check now exits 0. Audit 18/18.

Note: this repo's standards-check.yml is the 0.3.0-era template and does npm ci + npx nrstd audit, i.e. it runs the local devDependency with the npm cache rather than refetching from GitHub on every run. That is arguably better than the current template's npx --yes github:… and worth folding back into the standard — not changed here.