nightly-1943b145-ls250

CI Report:

https://ci-tests.linuxserver.io/linuxserver/beets/nightly-1943b145-ls250/index.html

LinuxServer Changes:

No changes

Remote Changes:

Refactor of layout utils (#6442)

This PR refactors import-match layout rendering by centralizing layout
selection and line generation in beets.util.layout, simplifying the
ShowChange display path, and tightening the layout
data model.

What Changed

• Added get_layout_lines() and get_layout_method() in
  beets.util.layout so layout selection (column vs newline) is
  handled in one place.
• Replaced Side from a mutable TypedDict with an immutable
  NamedTuple that exposes derived helpers (rendered, prefix/suffix
  widths, and rendered width).
• Simplified split_into_lines() from a 3-width tuple API to
  (first_width, width) and removed legacy last-line empty-string
  handling.
• Refactored beets.ui.commands.import_/display.py ShowChange to call
  get_layout_lines() directly and removed duplicate per-class
  layout-selection logic.
• Updated tracklist width calculation to use Side helpers and explicit
  width assignment via _replace(width=...).
• Reworked ShowChange tests into snapshot-style assertions for both
  newline and column layouts, and updated util layout tests to the new
  split_into_lines() signature.

Why

• Reduces duplicated wrapping/layout logic across UI code paths.
• Makes layout behavior easier to reason about and test at the utility
  boundary.
• Narrows the display layer to orchestration while keeping
  transformation/rendering logic in reusable utilities.
• Improves maintainability by moving from loosely typed dict mutation to
  a typed, self-describing data structure.