Integrate resources and CSS files to the Cambalache project

Author: marin-m

src/gui/interface.cmb

@@ -2,5 +2,9 @@
 <!DOCTYPE cambalache-project SYSTEM "cambalache-project.dtd">
 <!-- Created with Cambalache 0.96.3 -->
 <cambalache-project version="0.96.0" target_tk="gtk-4.0">
-  <ui filename="interface.ui" sha256="bd2fc50860841fd929b3577975f3988fb90d30f857f4ac4a9edd1fd7fcf71cf9"/>
+  <gresources filename="resources.gresource.xml" sha256="8a38c70ff299f1418349cab382cf40f877e5c7351777285ac2f7ace76baa274e"/>
+  <css filename="style.css"/>
+  <ui filename="interface.ui" sha256="d116f31b9586a137664e5be1e1700b26ff93ba6bd4333f615f68b7a3c3de191c">
+    <css-provider>style.css</css-provider>
+  </ui>
 </cambalache-project>

src/gui/resources.gresource.xml

@@ -1,4 +1,5 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version='1.0' encoding='UTF-8'?>
+<!-- Created with Cambalache 0.96.3 -->
 <gresources>
   <gresource prefix="/re/fossplant/songrec/">
     <file compressed="true" preprocess="xml-stripblanks">interface.ui</file>
@@ -12,4 +13,4 @@
     <file compressed="true" alias="search-symbolic.png">search-symbolic.png</file>
     <file compressed="true" alias="actions/128/search-symbolic.png">search-symbolic.png</file>
   </gresource>
-</gresources>
+</gresources>