feat(01-03): register ddhh_provider role with restricted capabilities

- Add DDHH_JM_Roles class with add_roles() and remove_roles() methods
- Role 'ddhh_provider' (Anbieter) can edit/delete own job_offers only
- Jobs go to pending status (publish_job_offers: false)
- No access to regular posts/pages (edit_posts/edit_pages: false)
- Can upload files for logos
- Integrated with Activator and Deactivator hooks

includes/class-deactivator.php

@@ -17,6 +17,9 @@ class DDHH_JM_Deactivator {
 	 * Deactivation logic
 	 */
 	public static function deactivate() {
+		// Remove custom roles
+		DDHH_JM_Roles::remove_roles();
+
 		// Flush rewrite rules
 		flush_rewrite_rules();
 	}