feat: migrate existing configs (#1)

Reviewed-on: #1
Reviewed-by: branch-buddy <branch-buddy@t00n.de>
Co-authored-by: Timo Behrendt <t.behrendt@t00n.de>
Co-committed-by: Timo Behrendt <t.behrendt@t00n.de>

README.md

@@ -1,3 +1,37 @@
-# renovate-configs
+# Renovate configs
 
-Reusable renovate config for T00N
+Reusable renovate configs, covering a number of use cases and opinionated "best practices".
+
+Usage:
+
+Your renovate.json
+
+```json
+{
+  "extends": [
+    "local>t.behrendt/renovate-configs:helm#1.0.0",
+    "local>t.behrendt/renovate-configs:k8s#1.0.0"
+  ]
+}
+```
+
+## Common
+
+Sets defaults such as the dependency dashboard.
+
+## k8s
+
+Keeps OCI image references for k8s deployments up-to-date. Requires the k8s manifests to be in the "./k8s" directory.
+
+## Helm
+
+Keeps the chart itself up-to-date as well as image references in chart values.
+Requires values to be in the "./values" directory. Supports both yaml and yaml.gotmpl for secrets.
+
+## Action
+
+Keeps your Gitea actions up-to-date. Also always pins to a commit hash, prevening attack vectors utilizing tag reusal.
+
+## Docker Compose
+
+Keeps Docker Compose service images up-to-date. Also always pins to a digest hash.