Add endpoint for getting all rules

[bracyw]

Description

Blocked by: #475

For context on Rules as a whole and what a Rule is see epic ticket: #455 . This ticket for adding an endpoint that returns all the Rules uploaded by an client.

This ticket is TBD blocked, as we are still deciding on some changes to rules manager struct. Making the route with an empty return statement would be something you could do to just get a PR up.

Acceptance Criteria

• Screenshots of postman call to new endpoint returning empty case and list of rules (more manual testing should be done by one screenshot is fine)
• Tests for the service

Proposed Solution

Add a route in main.rs, add a controller in rule_controller.rs, and add a new function to the rule manager that returns all the available rules.

Mocks

No response