Yonatan Beker 03c4af1c5b Use OpenAPI 5 management endpoints (#111) ...

## Summary
- Replace remaining /mgmt/openapi/latest management endpoint paths with
/mgmt/openapi/5
- Update matching integration-test mocks
- Update the contributing guide command template examples

## Testing
- cargo test --test routers --test retentions --test e2m --test
notification_testing --test integrations
- cargo test
- Manual staging smoke tests with -p stg:
  - cx -p stg e2m list -o json
  - cx -p stg e2m get 06e8c3ad-a1b4-422f-909a-da5a1e36fd42 -o json
  - cx -p stg e2m limits -o json
  - cx -p stg retentions list -o json
  - cx -p stg retentions status -o json
  - cx -p stg integrations list -o json
  - cx -p stg notifications routers list -o json
  - cx -p stg notifications routers get router_default -o json

Note: notifications test endpoints were skipped because they currently
do not work in the backend.

2026-05-25 16:29:13 +03:00

..

main.rs

Use OpenAPI 5 management endpoints (#111)

2026-05-25 16:29:13 +03:00