Various QoL fixes for Desktop App (#2999)

* Some ESLint fixes

* Add login/logout signal to API, clear mentions on logout and flush cookies on login/logout

* Fix issue where local and HTTP-only servers would not validate correctly

* Reduce noise of renderer logging, adjust a few local renderer logs to be louder when needed

* Fallback to beginning of hostname for servers that don't change the site name

* Fix Save Image crash

* Update the name for insecure servers too

* Fix test

* Fix lint

* Reduce repetition

e2e/utils/analyze-flaky-test.js

@@ -35,6 +35,7 @@ function analyzeFlakyTests() {
         return {commentBody, newFailedTests};
     } catch (error) {
         console.error('Error analyzing failures:', error);
+        return {};
     }
 }