A block namespace qualifies only its own body (a nested one is Outer.Inner),
mirrored in the kernel; a using names the project's namespace, never another
file's using; a global using is its own project's; a nested type is reached
by bare name only from inside its owner or a type deriving from it, through
any partial part; visible C# types are filtered before ranking.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Colby Mchenry