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

.eslintrc.json

@@ -48,9 +48,9 @@
                         "position": "after"
                     },
                     {
-                        "pattern": "(app|common|main|renderer){,/**}",
-                        "group": "external",
-                        "position": "after"
+                        "pattern": "@(app|common|main|renderer){,/**}",
+                        "group": "internal",
+                        "position": "before"
                     },
                     {
                         "pattern": "types{,/**}",