v0.2.6

Added

• Documentation page describing how barriers limit sorting to segments between
  side-effecting statements, and how to relocate a statement that should not be a
  barrier.

Changed

• Refresh the documentation: the installation instructions use uv-native commands, the
  class-method ordering reference and example now match the implementation, and the
  barrier relocation example is split into separate, color-tinted before and after
  blocks.