[Security Solution] Improve OpenAPI specs for Endpoint Exceptions API

[maximpn]

Epic: https://github.com/elastic/kibana/issues/200310

Summary

We need to make our API reference docs for Endpoint Exceptions API more user-friendly and usable. For that, we need to improve and polish the corresponding OpenAPI specs: enrich them with summaries, descriptions, examples of usage, etc:

• Add summaries for:
  • API endpoints
  • HTTP methods
• Add descriptions for:
  • API endpoints
  • HTTP methods
  • endpoint's parameters
  • requests
  • responses
  • shared schemas
• Add examples of usage of each API endpoint.
• Make sure the generated API reference documentation looks nice and correct on bump.sh.

API endpoints

The following public API endpoints were discovered during research:

• [ ] POST /api/endpoint_list
• [ ] POST /api/endpoint_list/items
• [ ] GET /api/endpoint_list/items
• [ ] PUT /api/endpoint_list/items
• [ ] DELETE /api/endpoint_list/items
• [ ] GET /api/endpoint_list/items/_find

[elasticmachine]

Pinging @elastic/security-detections-response (Team:Detections and Resp)

[elasticmachine]

Pinging @elastic/security-solution (Team: SecuritySolution)

[elasticmachine]

Pinging @elastic/security-detection-engine (Team:Detection Engine)

[elasticmachine]

Pinging @elastic/security-detection-rule-management (Team:Detection Rule Management)