Auto-animating loading indicator with three visual styles:
- Dots (braille rotation), Line (ASCII rotation), Bouncing (Larson scanner
with fade trail). Time-based frame calculation ensures each spinner runs
at its own speed independent of render triggers.
Configurable: SpinnerSpeed (.slow/.regular/.fast), BouncingTrackWidth
(.minimum/.default/.maximum/.fixed(Int)), BouncingTrailLength
(.short/.regular/.long), custom color.
Run loop upgraded from 100ms to 40ms polling (~25 FPS) to support
smooth animations.