Support AL2023 / AMIgen9 without downstream ver == 2023 Jinja workarounds

[tyesnyder-p3]

Downstream site-localization content currently requires repeated Jinja special-casing for Amazon Linux 2023 / AMIgen9 systems, e.g.:

{%- if ver == 2023 %}
{%- set ver = 9 %}
{%- endif %}

This workaround appears in multiple files and would be better handled upstream in Watchmaker so downstream content does not need to duplicate this logic.

Request:

• Add first-class AL2023 / AMIgen9 handling in Watchmaker platform detection
• Allow downstream Salt content to rely on normalized version mapping

Context:
Observed during Watchmaker validation work for AL2023 / AMIgen9 EC2s in a multi-distro customer-environment.

[lorengordon]

I feel like there is a bit of an xy problem here. We have something of a solution proposed, but not a sufficient description of the use case or the problem. Can you elaborate on the problem, in detail?