feat: add accepted HTTP status codes

[jhcpeixoto]

Summary

• add an HTTP monitor option for comma-separated accepted status codes such as 200, 204, 401, or 403
• persist the setting on monitors, import/export it, and expose it in the API schema
• make HTTP checks treat configured non-2xx codes as successful while preserving advanced body matching

Refs #2389, specifically the wishlist request for custom status-code response validation.

Verification

• npm run test:unit:services -- --runTestsByPath test/unit/providers/network/httpProvider.test.ts test/unit/validation/monitorValidation.test.ts
• npm run build:openapi
• npm run build (server)
• npm run build (client)
• npm run format-check (server)
• npm run format-check (client)
• targeted ESLint on changed server/client source files