style(web): shrink the resign button to secondary weight

At 44px and the same weight as "Gửi" it read as one of the two things to
do on your turn. It is neither: nobody is aiming for it, and it takes
two presses to do anything. Smaller and lighter, still its own outlined
block in danger colour on the right, so it stays easy to find.

web/src/lib/components/GameBoard.svelte

@@ -285,13 +285,18 @@
 	   it ends the game, subordinate because it is not the way to play it. */
 	.resign {
 		align-self: flex-end;
-		min-height: 44px;
-		padding: var(--space-2) var(--space-4);
+		/* Below the 44px the rest of the controls keep, deliberately: this is
+		   the one button here nobody is trying to hit, it takes two presses to
+		   do anything, and at full size it read as an offer rather than as the
+		   way out. Still its own outlined block in danger colour, so it is
+		   plainly findable rather than hidden. */
+		min-height: 32px;
+		padding: var(--space-1) var(--space-3);
 		border: 1px solid var(--border-strong);
 		border-radius: var(--radius-sm);
 		background: transparent;
 		color: var(--danger);
-		font-size: var(--text-4);
+		font-size: var(--text-3);
 		transition: background-color 150ms ease-out;
 	}