docs: Clarify that this is not a Unity package

[simon-lemay-unity]

Pull Request

Description

Add a small clarification in the README that this is not a Unity package. Users need to clone this repository separately from their Unity project. (I guess they can always just copy the module they want outright, but the rest of the instructions assume the path hierarchy of the repository so might as well tell them to just clone it.)

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Security fix
• Performance improvement

Provider Integration

• GameLift
• Multiplay
• PlayFab
• New Provider Integration
• General/Infrastructure
• Documentation

Related Issues

N/A

Changes Made

• Added a line to the README about cloning the repository separately from your Unity project.

Testing

• Tested locally
• Tested with actual provider integration
• Added/updated unit tests
• Verified no breaking changes

Security Checklist

• No credentials, API keys, or secrets committed
• Ran secret scan before committing
• Reviewed all changes for sensitive data
• Updated .gitignore if needed
• Followed security best practices from SECURITY.md

Code Provenance

• All code is original work created by me
• I have the right to submit this code under the Unity Companion License
• I did not copy code verbatim from provider documentation without attribution
• No proprietary or confidential code is included
• All third-party code is properly attributed and licensed

License Agreement

• I agree to license my contributions under the Unity Companion License
• I understand that Unity retains all rights to contributed code as specified in the license
• I have read and agree to the terms in CONTRIBUTING.md

Documentation

• Updated README.md if needed
• Updated CONFIGURATION.md for affected modules
• Added/updated code comments
• No documentation changes needed

Provider Terms Compliance

• Changes do not violate provider terms of service
• Changes do not encourage violation of rate limits or usage policies
• Provider names used descriptively without implying endorsement
• No provider logos or branding materials added

Additional Notes

N/A

Community Support Acknowledgment

• I understand this is a community-driven project
• I understand reviews are conducted on a best-effort basis
• I am willing to address review feedback