Restrict 'seen' command match to the beginning of a request

That one is by design, actually - when you address the bot ("BOTNAME: seen where"), the regex for "seen" becomes a lot freer than without addressing ("seen whee?"). You can see an example of the looser documentation via "BOTNAME: help Seen?". This *rarely* comes up (in 5+ years, you're the first to mention it), so it is unlikely that I'm going to fix this. With that said, if there ever comes a day of claimed syntax ("I've got this, no one else handle this line of text!"), we can fix it then.