Updated error message prefix to match the code Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Added sip grammar documentation, sidebar and footer One page per language element, each quoting the relevant sip.peg production and illustrated from the three bank elevator scenario. Examples were checked against the parser, including the ones shown as errors. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>