A test pins the app limit: the account at its limit is refused, a forge admin never is, and no limit asks nothing

src/actions/app_limit.ts is the quota on apps per account, and no test imports it.

Done, in test/app-limit.test.ts:

[ ] With the apps quota at 2 and two apps owned, requireAppRoom answers app_limit for a non-admin; with one owned it answers ok.
[ ] A forge admin at or over the limit answers ok.
[ ] With no quota set, any count answers ok.
[ ] appLimitWords reads "2 of 2 apps", and never more than the limit even when the count is above it.
[ ] Each assertion fails if its branch in requireAppRoom is removed.

Files: test/app-limit.test.ts only. Suggested: scout.

A test pins the app limit: the account at its limit is refused, a forge admin never is, and no limit asks nothing #6822