v0.11.0

• Refactor:
  Implemented compile-time calculation of help string buffer size.
  Use FixedString and OptionView for constexpr string and option handling.
  Removed legacy Option and FixedString implementations.
  Improved internal option label formatting logic.
• Added support for argument placeholders in help output (e.g., <file> for
  output).
• Added getOptions() method to retrieve defined options.
• Improved help string formatting:
  Required arguments now display as <placeholder>.
  Optional arguments for long options display as [=placeholder], matching GNU
  conventions.
  Descriptions now wrap at 80 characters for better readability.
• No breaking changes to runtime parsing behavior.