message: Allow ResolvedSpan to turn into an LSP Range
  Summary: In future diffs, we bridge the internals of the parser and LSP types. Add a simple "From" impl.
diff: @@ -500,6 +500,15 @@ impl Display for ResolvedSpan {
  }
  }
  +impl From<ResolvedSpan> for lsp_types::Range {
  + fn from(span: ResolvedSpan) -> Self {
  + lsp_types::Range::new(
  + lsp_types::Position::new(span.begin_line as u32, span.begin_column as u32),
  + lsp_types::Position::new(span.end_line as u32, span.end_column as u32),
  + )
  + }
  +}
  +
  impl ResolvedSpan {
  fn from_span(begin: LineCol, end: LineCol) -> Self {
  Self {
  