Prevent Duplicate Role Registration in Smart Contracts

[AryanGodara]

Detailed Information

The original issue was to prevent duplicate role registrations (e.g., registering as Inspector multiple times with the same wallet). The contract already had checks in place to prevent duplicate Inspector registrations, so that part was essentially fixed.

What’s Changed

Role Exclusivity:

• I added logic to enforce the fact that a wallet address can only have one role at a time.
• If a user is already an Inspector, they cannot register land (become a Land Owner).
  = If a user already owns land, they cannot register as an Inspector.

New Error Message:

• Added a specific revert message (Already registered for role) for attempts to register for a new role when already assigned another.

Tests:

• Added new tests to ensure users cannot register for a second role if they already have one.

Cairo Optimization:

• Replaced all while i < count loops with while i != count for better Cairo performance, (IDE suggestion; made sure that business logic doesn't change in any of them)

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Related Issues

Closes #357

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Type of Change

• 🐛 Bug fix or ⚙️ enhancement
• ✨ New feature or Chore (change with no new features or fixes)
• 📚 Documentation update

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Checklist (select as many as applicable)

• The code follows the style guidelines of this project.
• All new and existing tests pass.
• This pull request is ready to be merged and reviewed.

[fishonamos]

Lgtm!

[fishonamos]

LGTM!. There is an issue with the ci unrelated to your pr. Will fix them.