feat: full shadcn/ui component system with consistent typography

New components:
- ui/button.tsx — Button with primary/accent/surface/ghost/destructive variants
- ui/input.tsx — Input + Textarea with focus ring and CSS var theming
- ui/label.tsx — Radix Label with peer-disabled support
- ui/separator.tsx — Radix Separator
- ui/tooltip.tsx — Radix Tooltip with themed content
- ui/dialog.tsx — Radix Dialog replacing custom modal implementations
- ui/table.tsx — Table/TableHeader/TableBody/TableRow/TableHead/TableCell
- ui/typography.tsx — PageTitle/SectionHeading/Body/Muted/Caption/MonoCaption

Wired throughout all components:
- ConfirmDialog + FormModal migrated to Radix Dialog (focus trap, Escape, ARIA)
- All raw <button> → Button, <input>/<textarea> → Input/Textarea
- All repeated text patterns → typography components
- All hardcoded hex/rgba strings → COLOR constants

src/components/ui/dialog.tsx

@@ -0,0 +1,97 @@
+import { cn } from "@/lib/utils";
+import * as DialogPrimitive from "@radix-ui/react-dialog";
+import { X } from "lucide-react";
+import { forwardRef } from "react";
+
+export const Dialog = DialogPrimitive.Root;
+export const DialogTrigger = DialogPrimitive.Trigger;
+export const DialogPortal = DialogPrimitive.Portal;
+export const DialogClose = DialogPrimitive.Close;
+
+export const DialogOverlay = forwardRef<
+	React.ComponentRef<typeof DialogPrimitive.Overlay>,
+	React.ComponentPropsWithoutRef<typeof DialogPrimitive.Overlay>
+>(({ className, ...props }, ref) => (
+	<DialogPrimitive.Overlay
+		ref={ref}
+		className={cn(
+			"fixed inset-0 z-50 backdrop-blur-sm",
+			"bg-black/60",
+			"data-[state=open]:animate-in data-[state=closed]:animate-out",
+			"data-[state=closed]:fade-out-0 data-[state=open]:fade-in-0",
+			className,
+		)}
+		{...props}
+	/>
+));
+DialogOverlay.displayName = DialogPrimitive.Overlay.displayName;
+
+export const DialogContent = forwardRef<
+	React.ComponentRef<typeof DialogPrimitive.Content>,
+	React.ComponentPropsWithoutRef<typeof DialogPrimitive.Content>
+>(({ className, children, ...props }, ref) => (
+	<DialogPortal>
+		<DialogOverlay />
+		<DialogPrimitive.Content
+			ref={ref}
+			className={cn(
+				"fixed left-1/2 top-1/2 z-50 w-full max-w-md -translate-x-1/2 -translate-y-1/2",
+				"rounded-2xl p-6 shadow-2xl",
+				"[background:var(--bg-2)] [border:1px_solid_var(--border-2)]",
+				"data-[state=open]:animate-in data-[state=closed]:animate-out",
+				"data-[state=closed]:fade-out-0 data-[state=open]:fade-in-0",
+				"data-[state=closed]:zoom-out-95 data-[state=open]:zoom-in-95",
+				"data-[state=closed]:slide-out-to-top-[2%] data-[state=open]:slide-in-from-top-[2%]",
+				className,
+			)}
+			{...props}
+		>
+			{children}
+			<DialogPrimitive.Close
+				className={cn(
+					"absolute right-4 top-4 rounded-lg p-1 transition-colors",
+					"[color:var(--text-4)] hover:[color:var(--text-2)]",
+					"focus:outline-none focus:ring-2 focus:ring-[var(--accent)] focus:ring-offset-2 focus:ring-offset-[var(--bg-2)]",
+				)}
+			>
+				<X className="h-4 w-4" />
+				<span className="sr-only">Close</span>
+			</DialogPrimitive.Close>
+		</DialogPrimitive.Content>
+	</DialogPortal>
+));
+DialogContent.displayName = DialogPrimitive.Content.displayName;
+
+export function DialogHeader({ className, ...props }: React.HTMLAttributes<HTMLDivElement>) {
+	return <div className={cn("flex flex-col gap-1.5 pb-4 mb-4 [border-bottom:1px_solid_var(--border)]", className)} {...props} />;
+}
+
+export function DialogFooter({ className, ...props }: React.HTMLAttributes<HTMLDivElement>) {
+	return <div className={cn("flex justify-end gap-2 pt-4 mt-4", className)} {...props} />;
+}
+
+export const DialogTitle = forwardRef<
+	React.ComponentRef<typeof DialogPrimitive.Title>,
+	React.ComponentPropsWithoutRef<typeof DialogPrimitive.Title>
+>(({ className, ...props }, ref) => (
+	<DialogPrimitive.Title
+		ref={ref}
+		className={cn("text-sm font-semibold", className)}
+		style={{ color: "var(--text-1)" }}
+		{...props}
+	/>
+));
+DialogTitle.displayName = DialogPrimitive.Title.displayName;
+
+export const DialogDescription = forwardRef<
+	React.ComponentRef<typeof DialogPrimitive.Description>,
+	React.ComponentPropsWithoutRef<typeof DialogPrimitive.Description>
+>(({ className, ...props }, ref) => (
+	<DialogPrimitive.Description
+		ref={ref}
+		className={cn("text-sm", className)}
+		style={{ color: "var(--text-3)" }}
+		{...props}
+	/>
+));
+DialogDescription.displayName = DialogPrimitive.Description.displayName;