feat: plugin scaffold with dependency check

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01At3V6SjwbMe6eMzVGW3Hs7

phpcs.xml.dist

@@ -0,0 +1,23 @@
+<?xml version="1.0"?>
+<ruleset name="wp-lit-mcp">
+    <file>src</file>
+    <file>wp-lit-mcp.php</file>
+    <exclude-pattern>/vendor/*</exclude-pattern>
+    <arg value="sp"/>
+    <arg name="extensions" value="php"/>
+    <arg name="basepath" value="."/>
+    <rule ref="PSR12"/>
+    <rule ref="WordPress.Security"/>
+    <rule ref="WordPress.DB.PreparedSQL"/>
+    <rule ref="WordPress.DB.PreparedSQLPlaceholders"/>
+    <rule ref="WordPress.WP.AlternativeFunctions"/>
+    <rule ref="WordPress.WP.I18n">
+        <properties>
+            <property name="text_domain" type="array">
+                <element value="wp-lit-mcp"/>
+            </property>
+        </properties>
+    </rule>
+    <rule ref="PHPCompatibilityWP"/>
+    <config name="testVersion" value="8.1-"/>
+</ruleset>