[Task]: Rename verb-first fields in SDK action structs to noun-first naming

[renuka-fernando]

Please select the area the issue is related to

Area/Gateway (Routing, API deployment in gateway etc.)

Please select the aspect the issue is related to

Aspect/API (API backends, definitions, contracts, interfaces, OpenAPI)

Description

Created a discussion: #1307

[renuka-fernando]

Closing as this is done.