refactor: introduce platform registry and Typer CLI + version

[0xFustang]

Description

Introduces a platform descriptor registry to eliminate long if/elif chains across the codebase, and replaces argparse with Typer for a cleaner CLI with a dynamic command registry.

Changes

• Add platforms/registry.py: central platform descriptor registry; modules self-register instead of being dispatched via if/elif
• Add registry.py: dynamic Typer command registry
• Replace argparse with Typer + Rich for CLI and console output
• Refactor CLI commands into a commands/ subpackage (deploy/, rules/, sources/)
• Simplify convert.py, export.py, integrity.py, search.py by removing platform dispatch logic
• Add config.py for centralised config loading
• Add the ability to display the version of droid

Breaking Changes

The CLI interface has been redesigned from argparse to Typer. All commands now follow a droid <group> <command> structure so existing CI/CD pipelines jobs will need to be updated. This will be documented in the next release (v0.3.0) and the documentation will reflect the new changes.

Before	After
droid -s -p <platform> -r <path>	droid rules search -p <platform> -r <path>
droid -e -p <platform> -r <path>	droid rules export -p <platform> -r <path>
droid -i -p <platform> -r <path>	droid rules integrity -p <platform> -r <path>
droid -c -p <platform> -r <path>	droid rules convert -p <platform> -r <path>