Remove outdated async documentation from GNMIClient module:
- Remove async context manager from feature list
- Remove async usage example from class docstring
The client now only documents synchronous usage patterns.
- Replace placeholder deps with click, pygnmi, and rich for CLI functionality
- Add fabric-orch CLI entry point via project.scripts
- Configure hatchling as build backend with wheel/sdist targets
- Add ruff linter configuration for code quality
- Add dev dependency group with ruff
- Alphabetize yang module imports
The `Optional` type was imported from `typing` in `src/yang/paths.py`
but was not being used in the file. This change removes the unnecessary
import to clean up the code.
- Update the dependency installation command in the main README to use `uv sync` instead of `pip`, reflecting the project's package manager.
- Realign markdown tables in `src/yang/README.md` to improve raw text readability and consistency.
