…oes not own, and unbreak the #4116 ledger (#4117)

Two things, and the second is urgent.

## The fix (#4117)

`app.all(`${prefix}/auth/*`)` claimed a whole namespace and was TERMINAL: it
returned the auth service's response unconditionally, including better-auth's 404
for a path it does not implement, and the legacy `handleAuth` bridge's own
`handled: false` 404. That is #4088's shape. #4116's scan found it; the manual
greps that preceded that scan had not.

A 404 from better-auth, or `handled: false` from the dispatcher, now means "not
this mount's path" and the handler yields. The predicate is the dispatcher's OWN
`handled` flag wherever one exists — an explicit ownership answer beats inferring
one from a status; only the better-auth hand-off lacks such a flag, and there the
404 is the signal, exactly as in #4092.

What this buys here is narrower than #4092 and the code says so: it does NOT make
a later-registered Hono route reachable, because the `${prefix}/*` dispatcher
catch-all below is deliberately terminal (ADR-0076 OQ#9, #3576/#3608) and would
swallow one either way. It means an unowned `/auth/*` path now reaches that gated
`dispatch()` instead of dead-ending in a 404 built one mount earlier, so a domain
handler registered for it becomes reachable — which is this adapter's actual
extension mechanism. The first draft of the tests asserted the #4092 outcome and
failed, which is how the distinction got established rather than assumed.

## Unbreaking main

#4122 shipped the ledger declaring TWO ratcheted mounts here. Between its base
(974c6d4) and its merge, #4087/#4112 landed and DELETED the `/storage/*` bridge —
so the squash produced a main where the ledger declares a mount that no longer
exists, and `check:wildcard-fallthrough` fails on main with "DECLARED but not
found". That is my merge race, and this commit removes the entry.

Worth recording why the guard behaved well here: the stale-entry arm is what
caught it, immediately, on the first run against the new main. And #4112 reached
the same verdict about that wildcard independently, from the other direction —
"the wildcard was wider than the two routes it served". Two independent reads
landing on one defect is the argument for enumerating the shape rather than
finding it by eye each time.

Also extends `callsContinuation`: handing the continuation to a helper
(`yieldUnowned(c, next, …)`) now counts as yielding. Without that the checker
called this fix terminal — a false negative that would have pushed the compose
subtlety toward being duplicated at each call site instead of written once.

Guard: 7 yielding / 0 ratcheted / 5 exempt over 12 mounts. Self-test 17 cases.
adapters/hono 73 passed. Verified both defences bite: reverting the fix fails the
guard with the TERMINAL diagnostic and fails 2 of the 6 new tests. The 3 `tsc`
errors and 2 `eslint` rule-definition errors in this package are pre-existing,
measured identical on a clean tree.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013VZLsKypjrGhiLpio2uWKu