refactor: anonymous/free chat experience

- Enhanced lambda function formatting in `_after_commit` for better clarity.
- Simplified generator expression in `_match_condition` for improved readability.
- Streamlined function signature in `_eligible` for consistency.
- Updated imports and refactored anonymous chat routes to use a new agent creation method.
- Added a new function `_load_anon_document` to handle document loading from Redis.
- Improved UI components by replacing legacy structures with modern alternatives, including alerts and separators.
- Refactored quota-related components to utilize new alert structures for better user feedback.
- Cleaned up unused variables and optimized component states for performance.

surfsense_web/components/ui/empty.tsx

@@ -0,0 +1,94 @@
+import { cva, type VariantProps } from "class-variance-authority";
+
+import { cn } from "@/lib/utils";
+
+function Empty({ className, ...props }: React.ComponentProps<"div">) {
+	return (
+		<div
+			data-slot="empty"
+			className={cn(
+				"flex min-w-0 flex-1 flex-col items-center justify-center gap-6 rounded-lg border-dashed p-6 text-center text-balance md:p-12",
+				className
+			)}
+			{...props}
+		/>
+	);
+}
+
+function EmptyHeader({ className, ...props }: React.ComponentProps<"div">) {
+	return (
+		<div
+			data-slot="empty-header"
+			className={cn("flex max-w-sm flex-col items-center gap-2 text-center", className)}
+			{...props}
+		/>
+	);
+}
+
+const emptyMediaVariants = cva(
+	"mb-2 flex shrink-0 items-center justify-center [&_svg]:pointer-events-none [&_svg]:shrink-0",
+	{
+		variants: {
+			variant: {
+				default: "bg-transparent",
+				icon: "flex size-10 shrink-0 items-center justify-center rounded-lg bg-muted text-foreground [&_svg:not([class*='size-'])]:size-6",
+			},
+		},
+		defaultVariants: {
+			variant: "default",
+		},
+	}
+);
+
+function EmptyMedia({
+	className,
+	variant = "default",
+	...props
+}: React.ComponentProps<"div"> & VariantProps<typeof emptyMediaVariants>) {
+	return (
+		<div
+			data-slot="empty-icon"
+			data-variant={variant}
+			className={cn(emptyMediaVariants({ variant, className }))}
+			{...props}
+		/>
+	);
+}
+
+function EmptyTitle({ className, ...props }: React.ComponentProps<"div">) {
+	return (
+		<div
+			data-slot="empty-title"
+			className={cn("text-lg font-medium tracking-tight", className)}
+			{...props}
+		/>
+	);
+}
+
+function EmptyDescription({ className, ...props }: React.ComponentProps<"p">) {
+	return (
+		<div
+			data-slot="empty-description"
+			className={cn(
+				"text-sm/relaxed text-muted-foreground [&>a]:underline [&>a]:underline-offset-4 [&>a:hover]:text-primary",
+				className
+			)}
+			{...props}
+		/>
+	);
+}
+
+function EmptyContent({ className, ...props }: React.ComponentProps<"div">) {
+	return (
+		<div
+			data-slot="empty-content"
+			className={cn(
+				"flex w-full max-w-sm min-w-0 flex-col items-center gap-4 text-sm text-balance",
+				className
+			)}
+			{...props}
+		/>
+	);
+}
+
+export { Empty, EmptyHeader, EmptyTitle, EmptyDescription, EmptyContent, EmptyMedia };