labeling: mipmap for glyph textures

Create mipmap glyph textures and use them for rendering. Evaluate performance and visual result, comparing to /combining with anti-aliasing methods.

Locate the glyph texture creation and labeling-rendering entry points in the TypeScript codebase, then read how anti-aliasing is currently applied. Compare mipmapped glyph textures with existing or combined anti-aliasing approaches for performance and visual quality; done requires an implemented approach and recorded comparison results.

Written by the indexing model from the issue text.