feat: Add rotate(...)

[mrousavy]

// flip upside down (180°)
const upsideDown = image.rotate(180)
// tilt by an arbitrary angle (45°)
const tilted = image.rotate(45)
const whatever = image.rotate(3275)
// flip upside down (180°) using EXIF/Matrix flags, no actual buffer rotation
const upsideDownButFast = image.rotate(180, /* allowFastFlagRotation */ true)

FWIW the allowFastFlagRotation is significantly faster on iOS:

 (NOBRIDGE) LOG  Rotate 180° with allowFastFlagRotation=false took 11.66ms
 (NOBRIDGE) LOG  Rotate 180° with allowFastFlagRotation=true  took 0.33ms