feat: Add runtime validation for option types

[robertlipe]

This PR introduces a runtime validation mechanism to catch mismatches between declared and actual option types in arglist_t tables.

Key changes:

• A get_type() virtual method was added to the Option class hierarchy to enable runtime type identification.
• Validation logic was added to Vecs::validate_args to compare the declared argtype with the actual Option type, calling gbFatal on a mismatch.
• This addresses an issue where an incorrect argtype in the kalman filter's options was not caught at startup.
• The Option class hierarchy was refactored to fix various build errors, including breaking a circular dependency between defs.h and option.h.