Build, test, and debug regular expressions
Matches typed variable initialization statements like `int x = ` or `String name =`, capturing three named groups: leading indentation (indent), the variable type (type), and the identifier name (identifier). Requires at least one whitespace between the type and identifier, with flexible optional spacing around the assignment operator. Useful in code parsers, formatters, and transpilers (such as SuperJS) to detect and transform variable declarations in source code.