Draft: feat: add docs linter (vale)

Fixes #4

templates/vale.md

+# Vale
+
+```ini
+StylesPath = .gitlab/vale/styles
+MinAlertLevel = warning
+
+Packages = \
+    https://github.com/errata-ai/Microsoft/releases/latest/download/Microsoft.zip
+
+Vocab = Docs
+
+[*.md]
+BasedOnStyles = Vale, Microsoft, LibreTime
+
+# Exclude emoji shortcodes `:tada:`
+BlockIgnores = (:[a-z-_]+:)
+```