feat(locksmith) Add API to retrieve user metadata

[sudheerDev]

Description

• Add a new route to v2 controllers, readUserMetadata
• Add new API /:network/locks/:lockAddress/users/:userAddress

Issues

Enhancement to add support for https://github.com/unlock-protocol/unlock/issues/12481

Fixes # Refs #

Checklist:

• [x] 1 PR, 1 purpose: my Pull Request applies to a single purpose
• [ ] I have commented my code, particularly in hard-to-understand areas
• [x] I have updated the docs to reflect my changes if applicable
• [x] I have added tests (and stories for frontend components) that prove my fix is effective or that my feature works
• [ ] I have performed a self-review of my own code
• [ ] If my code involves visual changes, I am adding applicable screenshots to this thread

Release Note Draft Snippet

[sudheerDev]

@julien51 Made changes. Since when upserting data we are using network, thought it was better to use network when retrieving as well. Let me know of any changes required