- Replace `scc_cstring_from_cstr(scc_cstring_as_cstr(...))` with `scc_cstring_copy()` in lexer to fix memory leaks
- Extract macro expansion logic into separate `expand_macro.c` file
- Remove `expand_stack` parameter from `scc_pp_expand_macro()` function
- Add new parsing functions for macro replacement lists and arguments
- Add string utility functions for whitespace trimming and string joining
- Update memory stream documentation for clarity
- Change `scc_macro_table_t` to `scc_pp_macro_table_t` for consistency
- Rename `scc_pp_macro_create` to `scc_pp_macro_new` for naming convention
- Remove unused `scc_pp_compress_whitespace` function
- Update macro table function names: `scc_pp_find_macro` → `scc_pp_macro_table_get`, `scc_pp_remove_macro` → `scc_pp_macro_table_remove`
- Add new `scc_pp_macro_table_set` function for setting macros
- Update all function signatures to use new type name
- Remove commented-out whitespace compression code from implementation
- Rename `scc_lex_parse_is_identifier_header` to `scc_lex_parse_is_identifier_prefix` for clarity and add a TODO comment
- Update lexer to use the renamed function for consistency
- Fix package and dependency names in `cbuild.toml` (`smcc_pprocesser` → `scc_pprocesser`, `smcc_lex_parser` → `lex_parser`)
- Introduce new macro system with header file `pp_macro.h` defining macro types, structures, and management functions
- Refactor preprocessor initialization and cleanup in `pprocessor.c` to use new macro table and stream handling
- Replace legacy `hashmap` with `scc_pp_macro_table_t` for macro storage
- Improve error handling and resource management in preprocessor lifecycle
