i18n: translate to Japanese (Weblate)

Currently translated at 16.6% (3 of 18 strings)

Translation: SparkHome/Front-End
Translate-URL: http://i18n.a2x.pub/projects/sparkhome/front-end/ja/

i18n/ja.json

@@ -1,5 +1,12 @@
 {
-  "search" : {
+    "search": {
-    "placeholder" : "検索またはURLを入力"
+        "placeholder": "検索またはURLを入力"
-  }
+    },
-}
+    "Search": {
+        "engine-aria": "検索エンジンを切り替える",
+        "engine": {
+            "google": "Google"
+        },
+        "placeholder": "検索またはURLを入力"
+    }
+}