Add Class and Function System with Lambda Captures

[google-labs-jules]

This PR introduces a comprehensive update to the scripting language runtime and compiler to support:

1. Multi-function Code Generation: Refactored the single-stream emitter into a Module based system that holds multiple Function objects.
2. Class System: Added class keyword support, allowing definition of classes with methods and fields. Implemented OP_New to instantiate classes by creating objects and calling their constructors.
3. Lambda Captures (Closures): Implemented support for closures with captured variables using OP_MakeClosure and OP_LoadCapture. The emitter now detects and resolves captures from parent scopes.
4. Runtime Updates: Updated ScriptJit.h (Interpreter) to execute the new bytecode format, manage stack frames for function calls and closures, and handle object creation.

Key Changes:

• ScriptIr.h: Introduced Module and Function structs. Updated Emitter to work with functions and support capture resolution.
• ScriptAst.h: Added ClassStatement, NewExpression. Updated FunctionExpression to emit closures.
• ScriptJit.h: Rewrote Interpreter loop to support Module execution, OP_Call for closures, and OP_New.
• ScriptVariant.h: Added Closure variant type.

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PR created automatically by Jules for task 6205814732124054060 started by @telecomadm1145

[google-labs-jules]

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