ci(lint): replace yamllint action with make target, add kyaml mode

Drop the ibiqlik/action-yamllint GitHub Action in favour of a plain
`make yamllint` invocation. The new target runs yamllint (with -f
github for CI annotations) followed by yamlfmt -lint -quiet. Switch
yamlfmt to kyaml mode for Kubernetes-native YAML canonicalization.
Align exclude lists between .yamllint and .yamlfmt configs, tighten
yamllint coverage by removing config/default and config/manager from
the ignore list.

Co-authored-by: Claude <noreply@anthropic.com>

Author: wikkyk

.github/workflows/lint.yml

@@ -38,9 +38,7 @@ jobs:
         run: |
           sudo apt-get update
           sudo apt-get install -y yamllint
-      - uses: ibiqlik/action-yamllint@2576378a8e339169678f9939646ee3ee325e845c # v3.1.1
-        with:
-          format: github
+      - run: make yamllint
 
   actionlint:
     name: actionlint

.yamlfmt

@@ -1,17 +1,14 @@
-include:
-- metadata.yaml
-- .github
-- config/default
-- config/manager
-- config/samples
-- config/webhook
-- examples
 exclude:
-- .github/workflows
+# generated files
+- config/crd
+- config/certmanager
+- config/prometheus
+- config/rbac
+- out
 formatter:
   include_document_start: true
   indent: 2
   indentless_arrays: true
   max_line_length: 120
   retain_line_breaks: true
-  type: basic
+  type: kyaml

.yamllint

@@ -27,13 +27,10 @@ ignore:
 - config/certmanager
 - config/prometheus
 - config/rbac
-- config/manager
-- config/default
-- test/e2e
 - out
-- .*.yaml
-- .*.yml
-# these are clusterctl templates, not yaml
+# clusterctl templates use envsubst syntax that isn't valid yaml
+# TODO: find a way to lint these (preprocess with envsubst + dummy values?)
 - templates
-# github actions checked by actionlint
+- test/e2e
+# github actions have no document-start markers
 - .github/workflows

Makefile

@@ -82,8 +82,12 @@ mockgen: ## Generate mocks.
 
 .PHONY: yamlfmt
 yamlfmt: ## Run yamlfmt against yaml.
-	go tool yamlfmt -dry -quiet
-	go tool yamlfmt
+	go tool yamlfmt -verbose
+
+.PHONY: yamllint
+yamllint: ## Lint YAML files with yamllint and yamlfmt.
+	yamllint $(if $(GITHUB_ACTIONS),-f github) .
+	go tool yamlfmt -lint -quiet
 
 .PHONY: tidy
 tidy: ## Run go mod tidy to ensure modules are up to date