unify build, fix opening files when app is running

packaging/linux/rlogg.desktop

@@ -0,0 +1,14 @@
+[Desktop Entry]
+Version=1.0
+Type=Application
+Name=RLogg
+GenericName=Log Viewer
+Comment=Fast log file viewer with search, filtering, and highlighting
+# NOTE: Use absolute path for Exec to work in GUI file managers
+# The install.sh script will automatically set this to $HOME/.local/bin/rlogg
+Exec=/usr/local/bin/rlogg %F
+Icon=rlogg
+Terminal=false
+Categories=Development;Utility;
+MimeType=text/x-log;
+Keywords=log;viewer;search;filter;