✨ Focus the search field when opening the color tokens tab (#12345)

The color tokens tab of the color picker did not focus its search
field, so users had to click it before typing a token name. The token
dropdown of numeric inputs already focuses its search on open.

Closes #12344

AI-assisted-by: claude-opus-5-5

frontend/src/app/main/ui/workspace/colorpicker/color_tokens.cljs

@@ -310,6 +310,7 @@
                    :variant "comfortable"
                    :class (stl/css :search-input)
                    :default-value filter-term
+                   :auto-focus true
                    :on-change on-filter-tokens}]
        (if (seq sorted-tokens)
          [:div {:class (stl/css :color-tokens-inputs)}