feat: add BlogBodySanitizer for HTML sanitization on article save

- Implemented BlogBodySanitizer to clean HTML content before saving articles, ensuring security against XSS attacks.
- Added tests for BlogBodySanitizer to verify that unsafe tags and attributes are stripped from the content.
- Introduced ApiLeastPrivilegeTest to ensure that unauthorized users cannot access sensitive API routes, maintaining strict access control.

config/reference.php

@@ -653,7 +653,7 @@ use Symfony\Component\Config\Loader\ParamConfigurator as Param;
  *         time_based_uuid_node?: scalar|Param|null,
  *     },
  *     html_sanitizer?: bool|array{ // HtmlSanitizer configuration
- *         enabled?: bool|Param, // Default: false
+ *         enabled?: bool|Param, // Default: true
  *         sanitizers?: array<string, array{ // Default: []
  *             allow_safe_elements?: bool|Param, // Allows "safe" elements and attributes. // Default: false
  *             allow_static_elements?: bool|Param, // Allows all static elements and attributes from the W3C Sanitizer API standard. // Default: false