feat: preset environments

[rithulkamesh]

Users often need to set up similar development environments for different projects. This feature would allow them to save these environments as presets and quickly recreate them when needed.

For example, a user frequently creates Flask applications with PostgreSQL and SQLAlchemy. Instead of manually setting up the environment each time, they could use a preset.

Creating a Preset

yen preset webdev-psql -r requirements.txt

Using a Preset

yen create venv --preset webdev-psql

Additional Details

• Presets would be stored locally on the user's computer.
• Users could manage multiple presets for different project types.

[tusharsadhwani]

I think I'll go with yen preset create <name> so that we can add yen preset list and yen preset remove alongside.