feat: add setRequestToken and fetchRequestToken methods

[susnux]

Basically move them from server to this library, implementation only slightly changed for the non-dom case to keep service worker support. Otherwise same implementation and even tests are copied.

This allows us to have 1 place with the set token logic to reduce problems where the tokens get out of sync.

[codecov]

Codecov Report

❌ Patch coverage is 89.28571% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 65.75%. Comparing base (2ea86ef) to head (21b1c82).

Files with missing lines	Patch %	Lines
lib/requestToken.ts	89.28%	1 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #900      +/-   ##
==========================================
+ Coverage   60.71%   65.75%   +5.03%     
==========================================
  Files           4        4              
  Lines          56       73      +17     
  Branches       17       23       +6     
==========================================
+ Hits           34       48      +14     
- Misses         20       21       +1     
- Partials        2        4       +2     

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[ShGKme]

In the previous implementation it only used DOM API once to initiate the local state. Now every getRequestToken call gets it via DOM API.

What about checking _nc_auth_requestToken first and only as a fallback get it from the document to init the local state?

[susnux]

Then we still have a problem if updated outside of this library (aka old server versions).

[susnux]

(I mean we can do so and hope to update server in time - but still wonder how much overhead the DOM API call would be here)

[ShGKme]

What is the problem?

[susnux]

• If we change the token here in an app A
• Then another app B causes a token change in server
• Now this app A tries to get the token and gets the outdated because server only updated the DOM
• App A needs 2 useless requests to recover

[ShGKme]

Doesn't setToken on server emit the event even on a very old server?
nextcloud/server#17404

[susnux]

Ah yes seems to work.

[susnux]

let me adjust this

[susnux]

I have adjusted the implementation to use the cached version if possible.
Also prevented an event loop

[susnux]

(see fixup commit)