feat(dotnet-sdk): configurable client credentials token url

[alex-zyl]

Description

Makes token endpoint configurable.

References

#238

Review Checklist

• I have clicked on "allow edits by maintainers".
• I have added documentation for new/changed functionality in this PR or in a PR to openfga.dev [Provide a link to any relevant PRs in the references section above]
• The correct base branch is being used, if not main
• I have added tests to validate that the change in functionality is working as expected

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: alex-zyl / name: Alex Zyl (a203e06)

[rhamzeh]

Thanks for the PR @alex-zyl - sorry it's taking a bit longer to review, we're clearing through a backlog of .NET related changes and PRs and hopefully this week or early next week we can get this reviewed and merged

[alex-zyl]

No worries, @rhamzeh

Luckily the issue with hardcoded token endpoint subpath can be workedaround by providing own instance of http client where we can overwrite request url

[jamp-scp28]

Hey @alex-zyl, just an opinion; but seems to me we're not addressing the root issue, a better solution should involve Discovery, it might require some work though.

On the other hand, if a workaround is to be provided, I think the PR might introduce edge cases and breaking changes on clients relying already on that PathTemplate; just and idea but why just not adding a new variable to the ClientConfiguration.Credentials and use it for the PathTemplate if not null?

[curfew-marathon]

This PR has had no human activity for 90 days, so it has been marked lifecycle/stale.

This is automated backlog grooming, not a judgment on the work.

What happens next, unless there is activity:

• In 30 days, it will move to lifecycle/closing-soon
• 30 days after that, it will be closed

To keep it open, push a commit or leave a comment, and the clock will reset. For work that should not auto-close, such as an RFC or long-running experiment, ask a maintainer to add lifecycle/frozen.

[curfew-marathon]

This PR has had no human activity for 30 days since being marked lifecycle/stale, so it has now been marked lifecycle/closing-soon.

It will be closed in 30 days unless there is new activity.

If the work still matters, this is the moment to say so: leave a comment, push a commit, or ask a maintainer to add lifecycle/frozen if it should be kept open long-term.

If this work is no longer being pursued, no action is needed.