feat: Add syntax highlighting for IFC files
Added TextMate grammar for IFC syntax highlighting:
Syntax Elements:
- Entity IDs (#123) - highlighted as constants
- Entity types (IFCWALL, IFCPROJECT) - highlighted as type names
- Entity references (#N) - highlighted as variables
- Strings ('text') - string highlighting with escape sequences
- Numbers (integers, floats, scientific notation) - numeric constants
- Keywords (HEADER, DATA, ENDSEC, ISO-10303-21) - control keywords
- Section headers (FILE_DESCRIPTION, FILE_NAME, FILE_SCHEMA) - section keywords
- Special values ($, *, .T., .F., .U.) - language constants
- Comments (/* ... */) - comment highlighting
Created syntaxes/ifc.tmLanguage.json with complete IFC grammar.
Updated package.json to register grammar with language.
IFC files now have proper syntax coloring based on editor theme.
Ryan Schultz
95786a26ec