Replaces manual version updates across 12+ files with single-source
automated generation from futr.cabal.

Problem:
- Version information scattered across platform files, docs, and code
- Manual updates error-prone and time-consuming
- High risk of version inconsistencies

Solution:
- Template-based generation system in Setup.hs
- Auto-generated Version.hs module
- Version extracted from cabal file during build
- Template placeholders (@Version@, @VERSION_COMMA@, etc.)

Changes:
- Add template files for platform-specific configs
- Extend Setup.hs with version file generation
- Update Types.hs to use generated Version module
- Add comprehensive documentation and helper script
- Update .gitignore to exclude generated files

Benefits:
- Version updates now require single cabal file edit
- Zero risk of version mismatches
- Integrates seamlessly with existing build system
- CI/CD ready with automated generation

Usage: ./update-version.sh 0.4.0.0