Fix missing JSdoc

[peterpeterparker]

Is your feature request related to a problem? Please describe.

PR changes are hard to read because of repeated warning regarding the missing documentation.

Check warning on line 1535 in packages/candid/src/idl.ts
GitHub Actions / test (8.8.4, release-0.16, 20)

Missing JSDoc @param "x" description

Describe the solution you'd like

Add missing documentation or disable related CI job.

[krpeacock]

I've put this off long enough. Issue accepted 😄