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.
Add Lua, Python, Ruby, and Wren implementations of the binary_trees benchmark from the Computer Language Benchmarks Game. Update the benchmark runner to support multiple benchmarks with output validation, and fix the Wren compiler to handle the '\t' escape sequence in string literals.
The method function was incorrectly using the outer `compiler` pointer instead of the inner `methodCompiler` when emitting `CODE_LOAD_LOCAL` and its operand, causing incorrect bytecode generation for constructor receiver loading.
Add MAX_PARAMETERS constant set to 16 and extend VM bytecode instructions CODE_CALL_11 through CODE_CALL_16 to support the new limit. Introduce compile-time error messages when parameter or argument count exceeds 16 in function definitions, method declarations, subscript calls, and regular method calls. Add new native fiber call stubs fn_call9 through fn_call16 and register them in the core initialization. Include comprehensive test coverage for 9-16 parameter functions and methods, plus error tests for exceeding the limit in all contexts.
Add a check in the `field()` function to detect when a field is referenced outside of a class context. When `compiler->fields` is NULL (indicating no enclosing class), emit a clear error message "Cannot reference a field outside of a class definition." and assign a dummy field index of 255 to allow continued parsing with minimal cascading errors.
Also includes minor cleanup: remove two stale TODO comments about EOF checking and better error messages in `nextToken()` and `consume()`, and add a new test file `test/field/outside_class.wren` that verifies the error is produced for top-level field assignment.
Replace the fixed-size `MAX_PINNED` array of `Obj*` pointers with a dynamically allocated linked list of `PinnedObj` nodes, removing the 16-object limit and eliminating the `numPinned` counter. Update `pinObj` to accept a caller-provided `PinnedObj` stack variable and link it at the head of the list, and simplify `unpinObj` to pop the head without requiring the object argument. Adjust `wrenNewVM` to initialize the new `pinned` pointer to NULL, and modify `collectGarbage` to iterate the linked list instead of the array.
