fix(visualization): sharpen floor labels viewed from a distance (#4484)

Floor label textures now use the renderer's maximum anisotropy (the
flat viewing angle previously over-blurred the minified text) and the
white label text gets a subtle dark outline so it no longer fades into
the floor when mipmapped.

Co-authored-by: Christian Hühn <christian.huehn@maibornwolff.de>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>