feat: implement for-loops with proper scope management

- Add support for C-style for loops: for (init; condition; increment) { body }
- Implement three-level scoping: loop context + per-iteration contexts
- Add semicolon disabler for increment statements using RAII guards
- Support break/continue/return control flow with scope validation
- Fix semicolon handling in parser for flexible for-loop syntax

include/ast.hpp

@@ -6,6 +6,7 @@
 #include <Ast/ContainerInitExprs.hpp>
 #include <Ast/ControlSt.hpp>
 #include <Ast/ExpressionStmt.hpp>
+#include <Ast/ForSt.hpp>
 #include <Ast/FunctionCall.hpp>
 #include <Ast/functionParameters.hpp>
 #include <Ast/FunctionDefSt.hpp>