Prepare the Minecraft installation (#1)

Reviewed-on: https://git.badhouseplants.net/badhouseplants/minecraft-helmfile/pulls/1

.woodpecker/cdh.yaml

@@ -0,0 +1,31 @@
+# ----------------------------------------------
+# -- Check da helm pipeline
+# ----------------------------------------------
+when:
+  - event: cron
+    cron: nightly
+steps:
+  check badhouseplants:
+    image: ghcr.io/allanger/check-da-helm-helmfile-secrets:stable
+    secrets:
+      - sops_age_key
+    environment:
+      RUST_LOG: info
+    commands:
+      - cdh --kind helmfile -p $CI_WORKSPACE/helmfile.yaml -o
+
+  notification:
+    image: deblan/woodpecker-email
+    settings:
+      dsn:
+        from_secret: smtp_dsn
+      from:
+        address: woody@badhouseplants.net
+        name: Woody Woodpecker
+      recipients:
+        - allanger@badhouseplants.net
+      subject: CDH result
+      target: main
+      attachment: result.html
+    when:
+      - status: [success, failure]

.woodpecker/helmfile.yaml

@@ -0,0 +1,27 @@
+when:
+  event: push
+
+steps:
+  diff:
+    image: ghcr.io/helmfile/helmfile:canary
+    secrets: [sops_age_key, kubeconfig_content]
+    when:
+      - branch:
+          exclude:
+            - main
+    commands:
+      - mkdir $HOME/.kube
+      - echo "$KUBECONFIG_CONTENT" > $HOME/.kube/config && chmod 0600 $HOME/.kube/config
+      - helmfile diff --suppress-secrets
+
+  apply:
+    image: ghcr.io/helmfile/helmfile:canary
+    secrets: [sops_age_key, kubeconfig_content]
+    when:
+      - branch:
+          include:
+            - main
+    commands:
+      - mkdir $HOME/.kube
+      - echo "$KUBECONFIG_CONTENT" > $HOME/.kube/config && chmod 0600 $HOME/.kube/config
+      - helmfile apply