Force focus search field when entering Explore room page

Fix #353

imports/NeoChat/Page/JoinRoomPage.qml

@@ -19,18 +19,19 @@ Kirigami.ScrollablePage {
 
     title: i18n("Explore Rooms")
 
+    Component.onCompleted: identifierField.forceActiveFocus()
+
     header: Control {
         padding: Kirigami.Units.largeSpacing
         contentItem: RowLayout {
             Kirigami.SearchField {
+                id: identifierField
                 property bool isRoomAlias: text.match(/#(.+):(.+)/g)
                 property var room: isRoomAlias ? connection.roomByAlias(text) : null
                 property bool isJoined: room != null
 
                 Layout.fillWidth: true
 
-                id: identifierField
-
                 placeholderText: i18n("Find a room...")
             }