Well, now the functionality is all here, for real this time. I only needed a single pair of quotes rather than double - not sure why, but it means I can type in "#food" and get to that page directly.
... But this still kind of sucks for a solution. Having to type in "#food" rather than just "food" is unwieldy, twice the keystrokes, and would look really pathetic if I had to explain it to other users. Plus, it falls on me to use more plugins to add in hidden commands. Dokuwiki is 16 years old and no one else has asked for a better solution to this?
Some people might say I should be glad that I've at least gotten to the point of functionality, but this workaround is so contrived its almost not even worth it anymore. :/ I mean, Mediawiki does this by default without any plugins (though its page editor honestly feels stone age, which is what brought me here).
I know there's a plugin requests section, but; is there maybe a way I could get in touch with someone to commission a plugin? This is something that really should exist, and I'm willing to pay for it. The source plugin this is all based on is so close to what I'm looking for, and isn't even 50 lines of code, so it would probably be an easy and inexpensive edit for someone who knows what to look for.