feat: add positional arguments support to get commands

[jonathannorris]

Add positional arguments support to get commands

Implements FDN-561 to allow positional arguments as shorthand for the --keys flag in get commands.

What's Changed

Added support for positional arguments in:

• dvc variables get
• dvc features get
• dvc environments get

New Usage Patterns

# Before (still works)
dvc variables get --keys=var-one,var-two

# After (new options)
dvc variables get var-one var-two        # space-separated
dvc variables get var-one,var-two        # comma-separated
dvc features get feature-one feature-two # works for all commands

Key Features

✅ Backward compatible - existing --keys flag usage unchanged
✅ Precedence handling - positional args take priority over --keys
✅ Flexible input - supports both space and comma separation
✅ Updated help - new examples in command documentation
✅ DRY implementation - shared utility function for consistency

Testing

• Added focused test coverage for new functionality
• All existing tests continue to pass
• 187 tests passing with 0 failures

[Copilot]

Pull Request Overview

This PR adds positional argument support to get commands for variables, features, and environments, allowing users to specify keys as space-separated or comma-separated arguments instead of only using the --keys flag.

• Added a shared utility function parseKeysFromArgs to handle argument parsing with proper precedence
• Updated three get commands to support positional arguments while maintaining backward compatibility
• Added comprehensive test coverage for the new functionality

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/utils/parseKeysFromArgs.ts	New utility function for parsing keys from various argument formats
src/utils/parseKeysFromArgs.test.ts	Test coverage for the utility function
src/commands/variables/get.ts	Updated to support positional arguments and new examples
src/commands/variables/get.test.ts	Added test for positional argument functionality
src/commands/features/get.ts	Updated to support positional arguments and new examples
src/commands/features/get.test.ts	Added test for positional argument functionality
src/commands/environments/get.ts	Updated to support positional arguments and new examples
src/commands/environments/get.test.ts	New test file with comprehensive test coverage
oclif.manifest.json	Updated manifest with new command configurations

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[Copilot]

The comment is misleading. The code handles args.keys which is not necessarily the first positional argument, but rather a named argument. Consider updating the comment to accurately reflect what this code does.

Suggested change

	// Handle the first positional argument if provided
	// Handle the named argument 'keys' if provided