Version 2

[aiuto]

There is an accumulation of dumb behavior that could be fixed to make the package behave with less surprise. Fixing each is not hard, but will be backwards incompatible in a strict sense.

I'm inclined to tag what we have now as a branch, and bump to version 2 going forward.

• label it 2.0.rcN for the first few releases, where changes are settling
• Only test bazel 8+ compatibility?
• bump the bcr compatibility level? Bump the minimal runtime deps.
• allow tools in other languages, refactor release so we have a baseline and tool suites

[aiuto]

@cgrindel FYI