chore: refactor the global state and improve signer (#56)

* refactor

* update

* .

* rustfmt

* .

* .

* .

* .

* .

* add document

* .

* add logout

* handle error

* chore: update gpui

* adjust timeout

assets/icons/logout.svg

@@ -0,0 +1,3 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" fill="none" viewBox="0 0 24 24">
+  <path stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M20.25 12H9m11.25 0-4.5 4.5m4.5-4.5-4.5-4.5m-4.5 12.75h-5.5a2 2 0 0 1-2-2V5.75a2 2 0 0 1 2-2h5.5"/>
+</svg>

assets/icons/settings.svg

@@ -0,0 +1,4 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" fill="none" viewBox="0 0 24 24">
+  <path stroke="currentColor" stroke-linejoin="round" stroke-width="1.5" d="m7.878 5.214-.703-.162a1.77 1.77 0 0 0-2.123 2.123l.162.703a2 2 0 0 1-.84 2.114l-.854.57a1.728 1.728 0 0 0 0 2.876l.855.57a2 2 0 0 1 .84 2.114l-.163.703a1.77 1.77 0 0 0 2.123 2.123l.703-.162a2 2 0 0 1 2.114.84l.57.854a1.728 1.728 0 0 0 2.876 0l.57-.855a2 2 0 0 1 2.114-.84l.703.163a1.77 1.77 0 0 0 2.123-2.123l-.162-.703a2 2 0 0 1 .84-2.114l.854-.57a1.728 1.728 0 0 0 0-2.876l-.855-.57a2 2 0 0 1-.84-2.114l.163-.703a1.77 1.77 0 0 0-2.123-2.123l-.703.162a2 2 0 0 1-2.114-.84l-.57-.854a1.728 1.728 0 0 0-2.876 0l-.57.855a2 2 0 0 1-2.114.84Z"/>
+  <path stroke="currentColor" stroke-linejoin="round" stroke-width="1.5" d="M14.75 12a2.75 2.75 0 1 1-5.5 0 2.75 2.75 0 0 1 5.5 0Z"/>
+</svg>