Extension not usable after getting in a broken state

[ArquintL]

When the extension cannot be started (e.g. because an incompatible Gobra server has been installed), all Gobra IDE commands do not work (updating Gobra Tools or getting the Java path). This then requires to first clean the installation folder before Gobra tools are automatically updated during the next start.
Thus, errors while starting the extension should be handled more gracefully such that parts of the extension remain functional (those not requiring Gobra server for example)