feat: 彻底禁用 Flarum 邮件通知

- 从驱动层移除 EmailNotificationDriver，禁止所有邮件通知发送
- 新用户注册时自动关闭邮件通知偏好兜底
- 站点通知保持不变

composer.json

@@ -0,0 +1,24 @@
+{
+    "name": "metazone/disable-email-notifications",
+    "description": "彻底禁用 Flarum 邮件通知——从驱动层移除 EmailNotificationDriver，保留站点通知不受影响。",
+    "type": "flarum-extension",
+    "license": "MIT",
+    "require": {
+        "flarum/core": "^1.0"
+    },
+    "autoload": {
+        "psr-4": {
+            "MetaZone\\DisableEmailNotifications\\": "src/"
+        }
+    },
+    "extra": {
+        "flarum-extension": {
+            "title": "Disable Email Notifications",
+            "icon": {
+                "name": "fas fa-envelope",
+                "backgroundColor": "#e74c3c",
+                "color": "#fff"
+            }
+        }
+    }
+}