Regex Tester & Validator

Matches simple C-style assignment statements such as `variable = value;` by capturing the left-hand side (one or more non-whitespace characters), a literal ' = ', the right-hand side, and the terminating semicolon. Using capture groups $1 and $3, it is handy in editor find-and-replace to reverse assignments (e.g., replacing with `$3 = $1;`). The global and multiline flags allow processing every assignment across all lines of a file.