shadertoy-cli 2.1.5

.ststate is ShaderToy CLI's resumable debugging artifact.

It stores:
  - render dimensions
  - fixed frame rate
  - shader time and iFrame
  - lossless RGBA32F contents of persistent 2D buffer passes

The state is deterministic and independent of wall-clock playback.

Capture:
  shadertoy state capture --frame 300 -o target/frame300.ststate

Inspect:
  shadertoy state inspect target/frame300.ststate --json

Modify one buffer:
  shadertoy state set target/frame300.ststate \
    buffer-a=fixtures/known.png \
    -o target/modified.ststate

Resume:
  shadertoy render --state target/modified.ststate -o target/next.png