style(api-docs): clean up api documentation.

Previously, it was not possible to check request/response bodies samples in API documentation. This commit solves this error by refactoring the API documentation by using yaml for all api schemas/samples and decomposition of the open-api.yaml file.

- decompose the mod-search.yaml file.
- move all the paths into separate yaml files with corresponded folders inside paths folder.
- move all the parameters into separate yaml files inside the parameters folder.
- create yaml versions for all the examples.
- create yaml versions for all the schemas.
- delete example files with sample extension.
- delete schemas files with json extension.

Closes MSEARCH-546.

src/main/resources/swagger.api/parameters/sort-order-param.yaml

@@ -1,6 +1,6 @@
 in: query
 name: sortOrder
-description: Defines sorting order
+description: 'Defines sorting order'
 required: false
 schema:
   $ref: '../schemas/entity/sortOrder.yaml'

src/main/resources/swagger.api/paths/search-index/search-index-records.yaml

@@ -7,7 +7,7 @@ post:
     content:
       application/json:
         example:
-          $ref: '../../examples/request/indexRecordRequestBody.yaml'
+          - $ref: '../../examples/request/indexRecordRequestBody.yaml'
         schema:
           $ref: '../../schemas/request/indexRecordRequest.yaml'
   responses: