fix(ci): fix black/ruff failures, add CoC and PR template

- Fix Python formatting (sync no longer strips blank lines from .py files)
- Remove test_community_build.py (tests private sync module)
- Fix ruff warnings in test files
- Add CODE_OF_CONDUCT.md
- Add .github/PULL_REQUEST_TEMPLATE.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

plugins/wordpress/handlers/coupons.py

@@ -5,6 +5,7 @@ from typing import Any
 
 from plugins.wordpress.client import WordPressClient
 
+
 def get_tool_specifications() -> list[dict[str, Any]]:
     """Return tool specifications for ToolGenerator"""
     return [
@@ -219,6 +220,7 @@ def get_tool_specifications() -> list[dict[str, Any]]:
         },
     ]
 
+
 class CouponsHandler:
     """Handle coupon-related operations for WooCommerce"""