Restructure Compiler to use dynamic bytecode and constant buffers instead of
relying on ObjFn's fixed-size arrays. Move ObjFn creation to the end of
compilation, add wrenListAdd/Insert/RemoveAt helpers to wren_value, relocate
list capacity macros and ensureListCapacity into wren_value.c, and store a
Compiler pointer in WrenVM for GC safety during compilation.
When a class is defined, its superclass is not known until runtime since class definitions are imperative statements. This adds a new wrenBindMethod function that walks the bytecode of a method after it is bound to a class, adjusting LOAD_FIELD/STORE_FIELD indices to account for inherited fields and patching superclass dispatch targets. The newClass function now correctly accumulates numFields from the superclass chain, and the VM calls wrenBindMethod when binding methods to a class. Includes new test files for inherited field access and the is operator.
Replace the linked-list Scope structure with a flat Local array indexed by depth, enabling proper shadowing semantics where inner declarations correctly hide outer ones. Remove the PUSH_SCOPE/POP_SCOPE macros and the SymbolTable-based locals tracking, replacing them with a MAX_LOCALS (255) fixed-size array that stores variable name, length, and depth. Add four new test cases covering local/parameter collision, nested block scoping, global shadowing, and local shadowing to validate the new behavior.
