chore: make hover window focusable and update docs

lua/Trans/core/util.lua

@@ -175,7 +175,7 @@ end
 ---@param str string
 ---@return boolean
 function M.is_word(str)
-    return str:find('%W') == nil
+    return str:find '%W' == nil
 end
 
 ---@param list any[]

lua/Trans/core/window.lua

@@ -198,7 +198,7 @@ local default_opts = {
         -- zindex
         style     = 'minimal',
         border    = 'rounded',
-        focusable = false,
+        focusable = true,
         noautocmd = true,
     },
 }