Upgrade hono to 4.6.7 to fix Next 15

[JulianKingman]

I'd like to open a PR that upgrades hono from 4.4.4 to 4.6.7. Issue here: #526

I've patched it locally using pnpm, so that works for now... I tried forking and testing frog, but I had a bunch of issues getting tests to pass (env vars for APP_FID didn't seem to work for some reason...)

Anyway, per the contributing guidelines, starting the discussion here!