Tasks: * move `lex` method from `syntax/src/lib.rs` to `syntax/src/lexer.rs` * change the return type from `Vec<(SyntaxKind, SmolStr)>` to `Vec<(SyntaxKind, TextSize)>`
Tasks:
lexmethod fromsyntax/src/lib.rstosyntax/src/lexer.rsVec<(SyntaxKind, SmolStr)>toVec<(SyntaxKind, TextSize)>