Add C backend to nxc-frontend:
- Implement CEmitter with HIR-to-C translation
- Add emit_c() function for code generation
- Support function prototypes, statements, expressions, and control flow
- Generate C11-compatible code with proper type mapping
- Add main() wrapper generation for entry points
Extend driver crate with build pipeline:
- Add emit_c_from_frontend() to generate C source from HIR
- Add write_c_file() to write generated
Restructure nxc-cli crate:
- Extract main logic into lib.rs with main_entry() function
- Move nexacore binary to separate bin/nexacore.rs file
- Keep nxc binary in main.rs as thin wrapper
Add semantic analysis to compilation pipeline:
- Implement semantic analyzer with type checking and name resolution
- Add Type enum with Int, Float, Bool, String, Void, Struct, Function, Error variants
- Add typed AST nodes (TypedModule, TypedFunction
Add initial project structure for NexaCore programming language compiler:
- Create Cargo workspace with 4 crates (cli, driver, frontend, runtime)
- Add lexer with indentation-based tokenization and keyword support
- Add parser for modules, functions, structs, and basic expressions
- Implement CLI with build command and placeholder subcommands
- Add driver crate to orchestrate compilation pipeline
- Include .gitignore for Rust build
