Fixes some issues with the swagger documentation for the new multiple
files API endpoint (#24887) which were overlooked when submitting the
original PR:
1. add some missing parameter descriptions
2. set correct `required` option for required parameters
3. change endpoint description to match it full functionality (every
kind of file modification is supported, not just creating and updating)
The PKCE flow according to [RFC
7636](https://datatracker.ietf.org/doc/html/rfc7636) allows for secure
authorization without the requirement to provide a client secret for the
OAuth app.
It is implemented in Gitea since #5378 (v1.8.0), however without being
able to omit client secret.
Since #21316 Gitea supports setting client type at OAuth app
registration.
As public clients are already forced to use PKCE since #21316, in this
PR the client secret check is being skipped if a public client is
detected. As Gitea seems to implement PKCE authorization correctly
according to the spec, this would allow for PKCE flow without providing
a client secret.
Also add some docs for it, please check language as I'm not a native
English speaker.
Closes#17107Closes#25047