[quarto-web] Warn in PR when a .qmd has not been re-rendered for freeze update

[cderv]

From discussion in quarto-dev/quarto-web#1801

We should find a way for our preview GHA workflow to add in the issue comment published already the information that the file freezer has not been updated.

Easiest way would be to quarto inspect <file> and then find if frozen or not.

We don't report it per-se, but we can "guess"

• fileInformation : look for the file
• See if any codeCells
• if so, then yes it frozen and needs update.
• If not, look into all includeMap file if they have some CodeCell
• and same heuristic.

I don't know if this could be fast to do.

Maybe there is benefit of having quarto inspect report the information directly has it can know if a file has some code cells or not.

[cderv]

Depending on

• inspect: report state of freezer #13554

The work in quarto-web could be easier !