Mejorar reportes de errores

https://craftinginterpreters.com/scanning.html#error-handling
https://craftinginterpreters.com/parsing-expressions.html#syntax-errors

En este momento nuestros errores son muy básicos, no reportan ni en que linea sucedieron. Hay que darle más contexto al usuario para que pueda debuggear mejor su código.

Start with the error-handling guidance in scanning.html and the syntax-errors section in parsing-expressions.html. Trace the interpreter's scanner and parser entry points to find where errors are created and reported. Done means errors identify the line where they occurred and provide enough context to help debug the Lox code.

Written by the indexing model from the issue text.