The customer-manager from radekska

implement `GET /api/customers/<customer_id>/purchases`

add pagination for customer lists endpoints

handle `UNIQUE constraint failed: customers.telephone_number` when trying to add a customer with same telephone number

implement POST /api/customers/<customer_id>/purchases

implement REST API for /api/customers*

There will be three models on which the API will be based.

Both purchase and repair models have a one-to-many relationship with a customer.

Endpoints:

/api/customers
- GET /api/customers - return list of customers #17
  query parameters: limit TODO
- POST /api/customers - create new customer #20
  accept json
/api/customers/<customer_id>
- GET /api/customers/<customer_id> - return customer details #24
- PUT /api/customers/<customer_id> - edit customer details #25
- DELETE /api/customers/<customer_id> - delete customer and all it's relations #27
/api/customers/<customer_id>/purchases
- GET /api/customers/<customer_id>/purchases return list of purchases - #29
  query parameters: search, limit, filter TODO
- POST /api/customers/<customer_id>/purchases create new purchase
  accept json - #37
/api/customers/<customer_id>/purchases/<purchase_id>
~~- GET /api/customers/<customer_id>/purchases/<purchase_id> - return purchase details~~
- PUT /api/customers/<customer_id>/purchases/<purchase_id> - edit purchase details - #40
- DELETE /api/customers/<customer_id>/purchases/<purchase_id> - delete purchase details - #39
/api/customers/<customer_id>/repairs
- GET /api/customers/<customer_id>/repairs return list of repairs
  query parameters: search, limit, filter
- POST /api/customers/<customer_id>/repairs create new repair
  accept json
/api/customers/<customer_id>/repairs/<repair_id>
- GET /api/customers/<customer_id>/repair/<repair_id> - return repair details
- PUT /api/customers/<customer_id>/repair/<repair_id> - edit repair details
- DELETE /api/customers/<customer_id>/repair/<repair_id> - delete repair details

handle duplicated key not allowed in API response

2023/06/18 07:02:45 /home/appuser/app/repositories/customers.go:26 duplicated key not allowed
[8.628ms] [rows:0] INSERT INTO `customers` (`id`,`first_name`,`last_name`,`telephone_number`,`created_at`,`updated_at`) VALUES ('0acac6a1-1db6-46d6-85c5-f3d2a22a5203','Ra
dosław','Skałbania','509648347','2023-06-18 07:02:45.017','2023-06-18 07:02:45.017')
07:02:44 | 500 |     9ms |      172.18.0.2 | POST    | /api/customers                                    | duplicated key not allowed