Improve Flathub metainfo

org.opennumismat.OpenNumismat.metainfo.xml

@@ -2,7 +2,7 @@
 <component type="desktop-application">
   <id>org.opennumismat.OpenNumismat</id>
   <name>OpenNumismat</name>
-  <summary>Coin collecting software for organize and manage your own catalogue</summary>
+  <summary>Collecting software for organize and manage your own catalogue</summary>
   <description>
     <p>OpenNumismat is a handy and reliable application aimed at coin collectors, numismatists or amateurs looking to create a numismatics collection.</p>
     <p>With OpenNumismat, you will be able to organize and manage coin collection: create an advanced catalogue of your coins, wish and selling lists, view statistics for your collection.</p>
@@ -15,15 +15,21 @@
   <content_rating type="oars-1.1"/>
   <screenshots>
     <screenshot type="default">
+      <caption>Main window</caption>
       <image>http://opennumismat.github.io/images/screenMain.png</image>
     </screenshot>
     <screenshot>
+      <caption>Edit dialog</caption>
       <image>http://opennumismat.github.io/images/screenEdit.png</image>
     </screenshot>
     <screenshot>
+      <caption>Statistics chart</caption>
       <image>http://opennumismat.github.io/images/screenStatistics4.png</image>
     </screenshot>
   </screenshots>
+  <developer id="opennumismat.org">
+    <name>Janis</name>
+  </developer>
   <releases>
     <release date="2024-03-28" version="1.9.7"/>
     <release date="2024-01-18" version="1.9.6"/>