Fix ConfirmButton Enter/Space keydown bubbling to parent row handler

The button's onClick stopped mouse event propagation, but keyboard
Enter/Space fired a separate keydown event that bubbled to the
combatant row's onKeyDown, opening the stat block side panel instead
of arming/confirming the button.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/__tests__/confirm-button.test.tsx

@@ -195,4 +195,24 @@ describe("ConfirmButton", () => {
 		fireEvent.blur(button);
 		expect(screen.getByTestId("x-icon")).toBeTruthy();
 	});
+
+	it("Enter/Space keydown stops propagation to prevent parent handlers", () => {
+		const parentHandler = vi.fn();
+		render(
+			// biome-ignore lint/a11y/noStaticElementInteractions: test wrapper
+			<div onKeyDown={parentHandler}>
+				<ConfirmButton
+					icon={<XIcon />}
+					label="Remove combatant"
+					onConfirm={vi.fn()}
+				/>
+			</div>,
+		);
+		const button = screen.getByRole("button");
+
+		fireEvent.keyDown(button, { key: "Enter" });
+		fireEvent.keyDown(button, { key: " " });
+
+		expect(parentHandler).not.toHaveBeenCalled();
+	});
 });

apps/web/src/components/ui/confirm-button.tsx

@@ -67,6 +67,12 @@ export function ConfirmButton({
 		};
 	}, [isConfirming, revert]);
 
+	const handleKeyDown = useCallback((e: React.KeyboardEvent) => {
+		if (e.key === "Enter" || e.key === " ") {
+			e.stopPropagation();
+		}
+	}, []);
+
 	const handleClick = useCallback(
 		(e: React.MouseEvent) => {
 			e.stopPropagation();
@@ -95,6 +101,7 @@ export function ConfirmButton({
 						"bg-destructive text-primary-foreground rounded-md animate-confirm-pulse hover:bg-destructive hover:text-primary-foreground",
 				)}
 				onClick={handleClick}
+				onKeyDown={handleKeyDown}
 				onBlur={revert}
 				disabled={disabled}
 				aria-label={isConfirming ? `Confirm ${label.toLowerCase()}` : label}