Bug: File header comments get parsed as comment on first string (JS file format)

Hi! Thanks for this project!

Very low priority "bug":

When processing JS files of proper format, a header comment at the top of the file (like the sort used for copyright) gets included as the comment on the first string. I observed this when there was otherwise no comment on the first string.

## Potential Solution
Don't start parsing strings from the file until the line with "export" on it, or some other representative token where the hash begins.

(I'm not blocked on this, as I believe our project can remove the header comment, so no urgency from me!)

Start with the JavaScript-file parsing path and reproduce the case with a header comment before the first exported string. Confirm that the header is excluded from the first string's comment while actual string comments remain unchanged; the payload names no specific file or test.

Written by the indexing model from the issue text.