ListenerHTTP1's docs promise the same route map shape as ListenerHTTP so
a handler can be registered with both and served over either protocol.
That only holds if the dispatch rule is the same on both, so mirror it
here: exact `:path`, then the query-stripped path, then `fallback`, then
the synthetic 404.
The query-strip half is a behaviour change on this listener. `/thing?x=1`
previously 404'd even with `/thing` registered, while HTTP/1.1 routed it
— the asymmetry the shared route map was supposed to avoid. It also
matters for `fallback`: without it a query string would divert a
registered path to the fallback over HTTP/3 but not over HTTP/1.1.
`fallback` covers `routes` only. An unmatched WebTransport CONNECT is
still a 404 — a WT handler takes a session, not a request, so there is
nothing sensible to hand it.
MakeBidiHandler now reads the maps off `self` instead of taking them as
pointer parameters. `self` was already captured and unused, and this
mirrors how ListenerHTTP1 reaches its own state through Impl::owner.