tuiplay 0.7.20

Added

• Album cover-art view. 6 (show_cover) shows the cover of the currently
  playing song in the right pane. It follows the playing song and prefetches
  the art in the background. The renderer has three modes, cycled with Space
  while the cover view is focused: half-block (full color), braille
  (high-resolution monochrome), and shaded blocks. It scales the image with a
  Catmull-Rom kernel and corrects for the terminal cell aspect so the art is
  not stretched.
• A completely reworked fullscreen visualizer. Every mode now shares a vivid,
  reactive palette (vividHex): the spectral position sets the hue (bass warm,
  treble cool), loudness sets the brightness, a drifting phase breathes the
  scene, and a detected beat flashes the whole screen. The spectrum draws with
  half-block glyphs for double vertical resolution, so a small window still
  reads smooth. Two new modes replace the old ellipse and Lorenz modes: a
  radial bloom that radiates the spectrum from a pulsing center, and beat
  sparks that burst particles from the center on each beat (with an optional
  fading streak). The animation tick runs at about 30 fps.
• A [visualizer] config table that tunes every visualizer mode. Shared:
  hue_speed, beat_sensitivity. Spectrum: spectrum_smoothing,
  spectrum_peak_gravity, spectrum_tilt, spectrum_monstercat. Waveform:
  wave_falloff. Stereo: stereo_smoothing. Radial bloom: radial_decay,
  radial_reach, radial_core. Beat sparks: spark_life, spark_speed,
  spark_gravity (a negative value gives straight streaks), spark_count,
  and spark_trail (comet streaks). Each key is optional and falls back to a
  built-in default.

Changed

• The visualizer keeps its own vivid palette; the UI theme no longer changes
  it. The spectrum, waveform, radial bloom, and stereo spectrum now smooth
  their levels toward the previous frame, so bars glide and blooms fall off
  gradually instead of snapping. The spectrum peak caps fall under gravity.
• Song info (i) and artist info (I) now push onto the browse stack from any
  right-pane view, not only from the browse view.

Fixed

• The cover-art aspect ratio is corrected so the image is not stretched
  vertically.
• A late queue restore that paused freshly started playback is dropped.