Fix Activepieces branding with proper logo and text

- Change "Built with" to "Powered by" in ShowPoweredBy component
- Replace purple dot with actual Activepieces swirl logo in SVG
- Update favicon and logoIcon URLs to use SmoothSchedule branding
- Add light and dark mode versions of automation builder logo

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

activepieces-fork/packages/react-ui/src/components/show-powered-by.tsx

@@ -23,7 +23,7 @@ const ShowPoweredBy = ({ show, position = 'sticky' }: ShowPoweredByProps) => {
           },
         )}
       >
-        <div className=" text-sm transition">Built with</div>
+        <div className=" text-sm transition">Powered by</div>
         <div className="justify-center flex items-center gap-1">
           <svg
             width={15}