interpret crackle files as seg, fix skew in point cloud display

Adds point cloud support.

Adds bbox support.

Adds mesh and skeleton viewer.

Faster libcrackle.wasm

Style updates, faster crackle encoder.

Load libcrackle.wasm at page load

Fixes rendering after using text input. Faster crackle WASM.

Fixes painting selection on long Y axis.

fixes u64 array selection and painting