Fix meson/flatpak builds

data/icons/meson.build

@@ -1,13 +1,13 @@
 # Scalable icon
 install_data(
   '@0@.svg'.format(base_id),
-  install_dir: iconsdir / 'hicolor' / 'scalable' / 'apps',
+  install_dir: datadir / 'icons' / 'hicolor' / 'scalable' / 'apps',
   rename: '@0@.svg'.format(application_id)
 )
 
 # Symbolic icon
 install_data(
   '@0@-symbolic.svg'.format(base_id),
-  install_dir: iconsdir / 'hicolor' / 'symbolic' / 'apps',
+  install_dir: datadir / 'icons' / 'hicolor' / 'symbolic' / 'apps',
   rename: '@0@-symbolic.svg'.format(application_id)
 )

data/io.github.lemmygtk.lemoa.metainfo.xml.in

@@ -44,6 +44,6 @@
   </kudos>
   <developer_name>Bnyro</developer_name>
   <update_contact>bnyro@tutanota.com</update_contact>
-  <launchable type="desktop-id">@app-id@.desktop</launchable>
+  <launchable type="desktop-id">@APP_ID@.desktop</launchable>
   <platform>GTK 4</platform>
 </component>

data/meson.build

@@ -11,7 +11,7 @@ configure_file(
   output: '@BASENAME@',
   install: true,
   configuration: desktop_conf,
-  install_dir: metainfodir
+  install_dir: datadir / 'applications'
 )
 
 # Metainfo file
@@ -20,7 +20,7 @@ configure_file(
   output: '@BASENAME@',
   install: true,
   configuration: desktop_conf,
-  install_dir: metainfodir
+  install_dir:  datadir / 'metainfo'
 )
 
 configure_file(