v0.19.5

Fixed

• Elixir formatting no longer strips indentation, and no longer fights mix format. Elixir has no
  native backend and tree-sitter-elixir ships no indents.scm, so it runs on poly's built-in
  ELIXIR_INDENTS query — which modelled only do…end and fn…end. A file containing neither, such
  as a top-level %{} map, produced zero captures, and emit_reindented still trimmed every line and
  re-emitted it at level 0: a mix format-formatted checksum map came back flattened to column 0, and
  the two formatters then oscillated forever. Every Elixir package in the xberg-io polyrepo had drifted
  this way and failed mix format --check-formatted. Two changes: try_reindent_builtin now returns
  None when the query captures nothing at all, so a file poly has no structural model of falls
  through to whitespace normalization instead of being flattened; and (map), (list), (tuple) and
  (bitstring) are tagged @indent.auto so their interiors are emitted verbatim. They are
  deliberately not @indent — mix format aligns a wrapped => continuation at +4 under a +2 entry,
  which a level-counting model cannot express, so @indent would only shrink the oscillation rather
  than end it. Existing Elixir fixtures were all do…end/fn…end, the only constructs the query
  modelled, so the idempotency tests passed vacuously and never caught this.
  (crates/poly-core/src/engines/treesitter/indent.rs)