Allow silent install without application launch

Some users may want to install moolticute in an unattended silent
way, e.g. the following installs in silent mode skipping the creation of
a desktop icon:

    setupfile.exe /VERYSILENT /TASKS="!desktopicon"

However this will still run programs in the `RUN` section which executes
moolticute. This is undesired in an unattended setup, so we skip this
[on silent installs][1].

[1]: https://documentation.help/Inno-Setup/topic_runsection.htm#skipifsilent

win/installer.iss

@@ -53,7 +53,7 @@ Name: "Full"; Description: "Full installation"
 Name: "moolticute"; Description: "Moolticute"; Types: Full
 
 [Run]
-Filename: "{app}\moolticute.exe"; WorkingDir: "{app}"; Description: "Start Moolticute"; Flags: postinstall nowait runascurrentuser
+Filename: "{app}\moolticute.exe"; WorkingDir: "{app}"; Description: "Start Moolticute"; Flags: postinstall nowait runascurrentuser skipifsilent
 
 [Registry]
 Root: "HKCU"; Subkey: "SOFTWARE\Microsoft\Windows\CurrentVersion\Run"; ValueType: string; ValueName: "Moolticute"; ValueData: "{app}\moolticute.exe --autolaunched"; Flags: uninsdeletevalue