taffybar: add white outline to active workspace squircle

Target .workspaces .active .outer-pad with an inset box-shadow to
highlight the currently focused workspace pill.

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

dotfiles/config/taffybar/taffybar.css

@@ -183,6 +183,13 @@
 	color: rgba(255, 255, 255, 0.92);
 }
 
+.workspaces .active .outer-pad {
+	box-shadow:
+		inset 0 0 0 2px rgba(255, 255, 255, 0.75),
+		inset 0 1px 0 @pill-highlight,
+		0 10px 24px @pill-shadow;
+}
+
 .workspaces .active .overlay-box {
 	background-color: transparent;
 	border-color: transparent;