Add ADR for new repo

Signed-off-by: Brad Davidson <brad.davidson@rancher.com>

docs/adrs/k3s-charts.md

@@ -0,0 +1,23 @@
+# Stage Helm charts through k3s-charts
+
+Date: 2022-11-17
+
+## Status
+
+Accepted
+
+## Context
+
+The upstream Traefik chart repo has seen significant changes over the last month. Upstream has changed their repo structure, and actively removed content from deprecated locations,
+at least twice. In both cases, this immediately broke K3s CI, requiring changes to our build scripts in order to restore the ability to build, test, and package K3s.
+
+The K3s chart build process also makes several changes to the upstream chart to add values and break out the CRDs, using an ad-hoc set of scripts that are difficult to maintain.
+There are better tools available to perform this same task, if we did so in a dedicated repo.
+
+## Decision
+
+We will make use of the [charts-build-scripts](https://github.com/rancher/charts-build-scripts) tool to customize the upstream chart and stage it through a stable intermediate repo.
+
+## Consequences
+
+When updating Helm charts distributed with K3s, additional pull requests will be necessary to stage new versions into the k3s-io/k3s-charts repo, before updating the chart version in K3s.