Add Repository, Project, and Organization Caching Infrastructure

[David Bennett (dkbennett)]

Summary of the pull request

This change lays the groundwork for notifications and a more performant Repository Provider. It does not add much in the way of functionality on its own beyond updating the Settings UI for the Azure Extension. It is required for Notifications later.

References and relevant issues

Detailed description of the pull request / Additional comments

This change has 3 main categories of changes:

1. Addition of a data caching for organization, projects, and repositories. This is the main feature of this PR and it lays the groundwork for notifications and more performant Repository Provider functionality.

• Why cache this? Because for large organizations there are literally tens of thousands of repositories potentially available and this, and getting a list of all the active repositories of the user takes approximately twenty minutes for the Microsoft org. While this is probably a worst-case scenario, if it works for a large org like Microsoft it can probably work well for smaller orgs. Since repository activity and available data is unlikely to change frequently, this data can be cached and updated infrequently to minimize rest API calls needed and have a more responsive UI.
• Caching has cancellation options and is singled instanced. There is only ever one cache manager and it is updated as needed.
• Cache updates are very infrequent, starting at once every three days. This is an easily changeable value.
• Caching is infrequent, and can possibly get stale but this is unlikely. Should that be a problem there is a user force-update in the settings. Ideally this will never be needed if we get the caching rate reasonably correct but for now it is there as an escape hatch for any caching related issues users may experience to force an update.

2. Update/overhaul of Settings Controller for the extension

• Two implementations of the Settings Controller were added during development, and I merged the two and overhauled it a bit to scale better with multiple settings.
• The settings UI is not expected to be "final" and it probably has some tweaks people will want to make to it, but I think it is best those are smaller changes after this PR is completed.
• Retains the existing AI key, adds new caching, notifications, and an "open logs" button.

The namespace changes with DevBox have been resolved thanks to Kristen Schau (@krschau) fixing them in a separate PR which I merged in.

Validation steps performed

• Did a lot of manual and debug testing of the caching start/stop and interrupting it for various times and inspecting the data for correctness.
• Test updated the RepositoryProvider using the cached repository values, but did not include that in this change. It just added confidence that the repostitory caching changes were working as expected.
• Build and basic usage testing for other changes.
• All tests were rebuilt run and passed.

PR checklist

• Closes #xxx
• Tests added/passed
• Documentation updated