ui: add Radix tooltips to header icons

ui/src/components/ThemeSelector.tsx

@@ -1,6 +1,7 @@
 import { useState, useRef, useEffect } from 'react'
 import { Palette, Check } from 'lucide-react'
 import { Button } from '@/components/ui/button'
+import { Tooltip, TooltipTrigger, TooltipContent } from '@/components/ui/tooltip'
 import type { ThemeId, ThemeOption } from '../hooks/useTheme'
 
 interface ThemeSelectorProps {
@@ -97,16 +98,20 @@ export function ThemeSelector({ themes, currentTheme, onThemeChange }: ThemeSele
       onMouseEnter={handleMouseEnter}
       onMouseLeave={handleMouseLeave}
     >
-      <Button
-        variant="outline"
-        size="sm"
-        title="Theme"
-        aria-label="Select theme"
-        aria-expanded={isOpen}
-        aria-haspopup="true"
-      >
-        <Palette size={18} />
-      </Button>
+      <Tooltip>
+        <TooltipTrigger asChild>
+          <Button
+            variant="outline"
+            size="sm"
+            aria-label="Select theme"
+            aria-expanded={isOpen}
+            aria-haspopup="true"
+          >
+            <Palette size={18} />
+          </Button>
+        </TooltipTrigger>
+        <TooltipContent>Theme</TooltipContent>
+      </Tooltip>
 
       {/* Dropdown */}
       {isOpen && (

ui/src/components/ui/tooltip.tsx

@@ -0,0 +1,65 @@
+import * as React from "react"
+import * as TooltipPrimitive from "@radix-ui/react-tooltip"
+
+import { cn } from "@/lib/utils"
+
+function TooltipProvider({
+  delayDuration = 250,
+  ...props
+}: React.ComponentProps<typeof TooltipPrimitive.Provider> & {
+  delayDuration?: number
+}) {
+  return (
+    <TooltipPrimitive.Provider
+      data-slot="tooltip-provider"
+      delayDuration={delayDuration}
+      {...props}
+    />
+  )
+}
+
+function Tooltip({
+  ...props
+}: React.ComponentProps<typeof TooltipPrimitive.Root>) {
+  return <TooltipPrimitive.Root data-slot="tooltip" {...props} />
+}
+
+function TooltipTrigger({
+  ...props
+}: React.ComponentProps<typeof TooltipPrimitive.Trigger>) {
+  return <TooltipPrimitive.Trigger data-slot="tooltip-trigger" {...props} />
+}
+
+function TooltipContent({
+  className,
+  side = "bottom",
+  align = "center",
+  sideOffset = 8,
+  children,
+  ...props
+}: React.ComponentProps<typeof TooltipPrimitive.Content>) {
+  return (
+    <TooltipPrimitive.Portal>
+      <TooltipPrimitive.Content
+        data-slot="tooltip-content"
+        side={side}
+        align={align}
+        sideOffset={sideOffset}
+        className={cn(
+          "z-50 overflow-hidden rounded-md border bg-neutral-900 px-3 py-2 text-sm text-white shadow-md leading-tight min-h-7",
+          "data-[state=delayed-open]:animate-in data-[state=closed]:animate-out data-[state=closed]:fade-out-0 data-[state=delayed-open]:fade-in-0 data-[side=bottom]:slide-in-from-top-2 data-[side=left]:slide-in-from-right-2 data-[side=right]:slide-in-from-left-2 data-[side=top]:slide-in-from-bottom-2",
+          className
+        )}
+        {...props}
+      >
+        {children}
+        <TooltipPrimitive.Arrow
+          data-slot="tooltip-arrow"
+          className="fill-neutral-900"
+        />
+      </TooltipPrimitive.Content>
+    </TooltipPrimitive.Portal>
+  )
+}
+
+export { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger }