chore(desktop): zero eslint/typecheck debt + prettier pass (#39100)

- eslint --fix across src/ and electron/ (unused imports, import/prop sort, padding)
- flatten empty catch blocks in electron CJS; drop unused applyUpdatesPosixInApp arg
- add setMutableRef helper for imperative ref writes (react-compiler clean)
- move sidebar cookie persistence into an effect; extract scrollElementToBottom helper

apps/desktop/src/components/ui/textarea.tsx

@@ -5,13 +5,7 @@ import { cn } from '@/lib/utils'
 import { type ControlVariantProps, controlVariants } from './control'
 
 function Textarea({ className, size, ...props }: React.ComponentProps<'textarea'> & ControlVariantProps) {
-  return (
-    <textarea
-      className={cn(controlVariants({ size }), 'min-h-16', className)}
-      data-slot="textarea"
-      {...props}
-    />
-  )
+  return <textarea className={cn(controlVariants({ size }), 'min-h-16', className)} data-slot="textarea" {...props} />
 }
 
 export { Textarea }