Add a PHPCS file.

Author: Jaesin

phpcs.xml.dist

@@ -0,0 +1,29 @@
+<?xml version="1.0"?>
+
+<ruleset name="Apigee API Catalog coding standards">
+  <exclude-pattern>*/.git/*</exclude-pattern>
+  <exclude-pattern>*/config/*</exclude-pattern>
+  <exclude-pattern>*/css/*</exclude-pattern>
+  <exclude-pattern>*/js/*</exclude-pattern>
+  <exclude-pattern>*/vendor/*</exclude-pattern>
+  <exclude-pattern>\.md</exclude-pattern>
+
+  <rule ref="Drupal"/>
+
+  <!-- Copyright header must be visible on all PHP files, including classes in a namespace. -->
+  <rule ref="Drupal.Commenting.FileComment.NamespaceNoFileDoc">
+    <severity>0</severity>
+  </rule>
+  <!-- Annotation classes still contains snake case variable names. -->
+  <rule ref="Drupal.NamingConventions.ValidVariableName.LowerCamelName">
+    <severity>0</severity>
+  </rule>
+  <!-- Core doesn't conform to this standard.
+       @see: https://www.drupal.org/project/coder/issues/2803251
+       @see: https://www.drupal.org/project/drupal/issues/1158720
+       -->
+  <rule ref="Drupal.Commenting.FunctionComment.TypeHintMissing">
+    <severity>0</severity>
+  </rule>
+
+</ruleset>