This PR has a large blast radius because it takes the final step and bumps up the Controller to be fully async.
We have historically done a piece-by-piece update, so all operations were already async but the controller interface was kept synchronous.
With this update, the controller is now fully async and all tests are updated.
Most places where the new C# compiler warns about function names not ending in `Async` were also adressed, giving a massive refactor change.
Functionally, no changes are done.
This adds a nonce to the refresh token such that each request to obtain a refresh token must now also provide a matching nonce.
When using non-persisted logins, the request to the server is the same, but the "remember me" flag toggles a shorter duration for the refresh token.
The FE can then store the nonce in either local storage for persisted logins or in session storage for non-persisted logins.
The default is currently to always issue refresh tokens with a nonce, but this can be toggled with the JWT configuration.
The ngax client does not have the non-persisted login so it stores the nonce in local storage, using a name that is compatible with ngclient so the user can swap between them without needing to re-login.
The server util was updated to also store the nonce.
This fixes#6451
Introduces a `DuplicatiServerClient` to interact with the Duplicati server API, including authentication and various V1/V2 endpoints.
Adds `ServerCredentialType` to specify the authentication mechanism (Password or Token).
Includes a usage example to demonstrate client capabilities.
Kenneth Skovhede