feat(1b): add lint/format toolchain — lint devshell + scripts/lint.sh + ruff/yamllint config

.yamllint.yaml

@@ -0,0 +1,20 @@
+# yamllint config for cc-ci YAML (.drone.yml etc.). Phase 1b RL1.
+# Lenient on cosmetics (line length, comment spacing); strict on real errors (syntax, duplicate
+# keys, tab indentation). `truthy` is relaxed because Drone uses bare on/off-style scalars.
+extends: default
+
+rules:
+  line-length: disable
+  document-start: disable
+  comments:
+    min-spaces-from-content: 1
+  comments-indentation: disable
+  truthy:
+    check-keys: false
+  braces:
+    max-spaces-inside: 1
+
+ignore: |
+  secrets/
+  cc-ci-secrets/
+  .sops.yaml