Implement versioned feature flags standard

We need a way to be able to enable features in the wallet (and any other app with numeric versioning) based on version number. We should define a standard knowing our numeric versions in the wallet are `x.y.z` for production and `x.y.z.r` for RCs.

It should be additive only, so that we dont break wallet versions in production

No files, tests, or entry points are named. Start by surveying the TypeScript packages for wallet version parsing and feature-flag usage, then confirm how x.y.z and x.y.z.r versions should be handled. Done means the additive-only versioned feature-flag standard and its implementation scope are defined.

Written by the indexing model from the issue text.