List the action definitions your app has declared

Returns the in-app actions your app has declared, so your creator surface can render a row per action and offer the creator Fanvue's native pricing dialog for each one.

This is the read to build that page on. `GET /experiences/{experienceUuid}/actions` serves the *priced* per-experience catalogue, so an action the creator has not priced yet does not appear there at all — it cannot tell you what you have declared.

Owner app only: `appUuid` must be the app whose credentials make the call, otherwise 403. Scoped to the creator the call is made on behalf of, through their install: a caller whose user has not installed the app gets 404, never another app's or another creator's declarations.

**No amount of any kind is served here** — not the creator's price, not a suggestion, not a currency. Price is served only by `GET /experiences/{experienceUuid}/actions`.

Definitions you have withdrawn are omitted. An empty `definitions` array means you have declared nothing; a failure to read them is a 502, never an empty list.