- Added `display.shimmer` setting (`classic`, `kitt`, `disabled`) with default `classic` and UI metadata.
- Added shimmer mode resolution with defaulting plus classic/KITT intensity tier profiles and thresholds.
- Added `getFgAnsi` handling across shimmer compilation and progress-bar themes, with fallback ANSI output defaults.
- Reworked shimmer rendering to coalesce same-tier segments, cache palettes by symbol, and map disabled mode to mid-tier.
- Tuned loader timing to a 16ms render interval and 80ms spinner stepping for smoother ~60fps updates.