Automated version bumper

[rugulous]

We could do with a nicer way of version numbers - currently we have to update our local version and remember to also update the sample version. When the update goes live we also have to remember to update the config files there.

I'm thinking we could automate this as long as we follow a certain set of rules. Given a version number like 1.0.1:

• Each pull request to main increases the furthest-right number by one - 1.0.2, 1.0.3, and so on
• When a Milestone is completed (or when we do a new release), the version number is set to the release number - release 3.0.3 would update 1.0.1 -> 3.0.3

We still need to factor dev into this, however. My thinking is that each merge to dev takes the current version of main and bumps the furthest-right number, finishing by appending a b to the end. If main is 1.0.1 then a new PR to dev becomes 1.0.2b, main is 3.1.7 then dev is 3.1.8b, etc

[rugulous]

Release may be easier, there are hooks for both but publishing a release feels more absolute than closing a milestone!

[rugulous]

Could hook into the agent created in #255 to do this?