Implement Strict Syntax Mode for Translation

[yaskhan]

This change implements the requested Strict Syntax Mode. It introduces a new CLI flag --strict-syntax-mode that enforces modern Python 3.12+ typing standards and requires explicit annotations to eliminate implicit Any types in the transpiled V code.

Key changes:

• TranspilerConfig now includes strict_syntax_mode.
• main.py supports the new flag and re-raises SyntaxError for better error reporting.
• TranslatorBase and its subclasses have access to the configuration.
• ClassesMixin rejects Generic[T] inheritance in strict mode.
• AssignmentsMixin and FunctionsMixin require explicit annotations for targets inferred as Any.
• TypeInference now collects function return types.
• ModuleMixin ensures top-level assignments are correctly processed and checked.
• New test file py2v_transpiler/tests/test_strict_syntax.py verifies all strict mode requirements.

Fixes #204

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PR created automatically by Jules for task 4321059608732374860 started by @yaskhan

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[code-input]

Pull request #221 has conflicts that needs to be resolved.
You can resolve it at codeinput: 0d9f0977-1ea1-4692-9f1e-138f548caa04.

[code-input]

Pull request #221 has conflicts that needs to be resolved.
You can resolve it at codeinput: 7b19d3e1-49a3-4f05-825e-f20cf1c478ad.