Update typing for some of the extensions code.

Review Request #14633 — Created Oct. 8, 2025 and updated — Latest diff uploaded

Information

Djblets
release-5.x

Reviewers

This updates the typing for djblets.extensions.extension and
djblets.extensions.manager, moving to some modern typing constructs
and improving type safety for middleware.

This work is in preparation for some changes to ExtensionManager to
reduce side effects during reloading.

Unit tests pass.

Commits

Files