Code refactoring (#2785)

* chore: pretty theme menu in sidebar

* refactor: renaming component templates

* refactor: create custom `a-statistic` component

* fix: display button text only on large screens

* chore: remove loading background in overview page

* fix: show `Version` text when xray version is unknown

web/translation/translate.en_US.toml

@@ -67,6 +67,9 @@
 "emptyReverseDesc" = "No added reverse proxies."
 
 [menu]
+"theme" = "Theme"
+"dark" = "Dark"
+"ultraDark" = "Ultra Dark"
 "dashboard" = "Overview"
 "inbounds" = "Inbounds"
 "settings" = "Panel Settings"