Module registry 

Port of internal/config/versions.go: the version registry, the upgrade walker, and loadAndUpgrade.

Constants

LATEST_VERSION

The current schema version — the version the upgrade walker converges to.

Functions

load_and_upgrade

Constructs the declared version’s struct, unmarshals data into it, applies defaults, and walks the upgrade chain to the latest config.

supported_versions

Returns the registered config versions in ascending order, formatted for error messages (e.g. “1, 2”).

walk

Upgrades cfg to the latest version by repeated single-step upgrades. It terminates when a step reports Upgrader::is_terminal (the Rust replacement for the Go original’s pointer-identity check — see versions::Upgrader::is_terminal’s doc comment). The bound guards against a mis-implemented, non-progressing upgrade.