fix: add missing --plugins-path option to create command

[cestlarumba]

Summary

The --plugins-path option was listed in OPTION_GROUPS and expected as a parameter in the create() function, but was never defined as a @click.option decorator.

Problem

Users trying to use --plugins-path would get an "unrecognized option" error, even though the option was documented in the help text groupings.

Solution

Added the missing @click.option decorator for --plugins-path to the create command.

Testing

• Verified composer-dev create --help now shows --plugins-path in the "Environment options" group
• Confirmed the option is properly passed to the create() function
• All 155 unit tests pass ✅

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