Build, test, and debug regular expressions
This regex validates lines in a custom geometry/annotation definition format with multiline support. It matches four command types: 'a' or 'c' followed by a quoted name and one or more coordinate pairs like (x, y), 'g' as a standalone command, and 'r' followed by a quoted string. Useful for parsing configuration files that define shapes, regions, or spatial annotations with named identifiers and numeric coordinates.