UserOdooAgent Model

[amjithtitus09]

Proposed Changes

• Create a UserOdooAgent Model to store the user and odoo agent 1-1 mapping
• Removed odoo_agent_id field from User model
• Moved User viewset logic out to signals

Associated Issue

• Link to issue here, explain how the proposed solution will solve the reported issue/ feature request.

Architecture changes

• Remove this section if not used

Merge Checklist

• Tests added/fixed
• Update docs in /docs
• Linting Complete
• Any other necessary step

Only PR's with test cases included and passing lint and test pipelines will be reviewed

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