PackageDetail: toggle pattern for Compare button inCart state

Replaces the earlier inert selected-state treatment. Now:
- Button keeps its default soft/secondary chrome in both states — no
  separate brand-tinted visual.
- When `inCart=true`, a leading CheckRoundedIcon is added and the
  label swaps from "Compare" to "Added".
- Button remains clickable; `onCompare` is invoked in both states.
  Caller treats it as a toggle — add when absent, remove when present.
- aria-pressed reflects the state for SR users; aria-label spells
  "Add to comparison" / "Remove from comparison" explicitly.

Demo route swaps `basket.add()` for `basket.toggle()` on the handler
so a second click removes the package from the comparison basket.

Simpler visual (less space, one chrome to maintain) and a clearer
interaction — the user can undo directly from the detail panel
rather than hunting for CompareBar.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/organisms/PackageDetail/PackageDetail.tsx

@@ -55,9 +55,9 @@ export interface PackageDetailProps {
   /** Whether the compare button is in loading state */
   compareLoading?: boolean;
   /** Whether this package is already in the comparison basket. When true,
-   *  the Compare button swaps to an "In comparison" selected-state (soft
-   *  brand tint + check icon) and is inert — removal happens via the
-   *  CompareBar, not this button. */
+   *  the Compare button swaps its label to "Added" and adds a leading check
+   *  icon. The button remains clickable — the caller is expected to treat
+   *  `onCompare` as a toggle (add when not in cart, remove when in cart). */
   inCart?: boolean;
   /** Custom label for the arrange CTA button (default: "Make Arrangement") */
   arrangeLabel?: string;
@@ -219,42 +219,25 @@ export const PackageDetail = React.forwardRef<HTMLDivElement, PackageDetailProps
             >
               {arrangeLabel}
             </Button>
-            {onCompare &&
-              (inCart ? (
-                // Selected-state: soft brand tint + check icon. Inert
-                // (disabled + aria-disabled) — removal happens via the
-                // CompareBar, not this button. sx override keeps the
-                // brand tint instead of the default greyed-disabled look.
-                <Button
-                  variant="outlined"
-                  color="secondary"
-                  size="large"
-                  disabled
-                  startIcon={<CheckRoundedIcon />}
-                  aria-label="Already in comparison"
-                  sx={{
-                    flexShrink: 0,
-                    '&.Mui-disabled': {
-                      bgcolor: 'var(--fa-color-brand-50)',
-                      borderColor: 'var(--fa-color-brand-300)',
-                      color: 'var(--fa-color-text-brand)',
-                    },
-                  }}
-                >
-                  In comparison
-                </Button>
-              ) : (
-                <Button
-                  variant="soft"
-                  color="secondary"
-                  size="large"
-                  loading={compareLoading}
-                  onClick={onCompare}
-                  sx={{ flexShrink: 0 }}
-                >
-                  Compare
-                </Button>
-              ))}
+            {onCompare && (
+              // Same soft/secondary chrome in both states; when the package
+              // is in the basket a leading check icon appears and the label
+              // changes to "Added". Click is a toggle — caller decides to
+              // add or remove based on the `inCart` it's passing in.
+              <Button
+                variant="soft"
+                color="secondary"
+                size="large"
+                loading={compareLoading}
+                startIcon={inCart ? <CheckRoundedIcon /> : undefined}
+                onClick={onCompare}
+                aria-pressed={inCart}
+                aria-label={inCart ? 'Remove from comparison' : 'Add to comparison'}
+                sx={{ flexShrink: 0 }}
+              >
+                {inCart ? 'Added' : 'Compare'}
+              </Button>
+            )}
           </Box>
         </Box>
 

src/demo/apps/arrangement/routes/Packages.tsx

@@ -21,11 +21,13 @@ export function PackagesRoute() {
 
   if (!provider || !bundle) return <Navigate to="/" replace />;
 
-  // Compare CTA on the PackageDetail panel just adds the selection to the
-  // basket. The floating CompareBar (mounted in App.tsx) handles navigation
-  // and removal once the user has 2+ packages selected.
+  // Compare CTA on the PackageDetail panel toggles the selection in the
+  // basket — adds when absent, removes when present. The button's visible
+  // state (Compare / Added + ✓) reflects `isSelectedInCart` below. The
+  // floating CompareBar (mounted in App.tsx) handles navigation once the
+  // user has 2+ packages selected.
   const handleCompare = () => {
-    if (selectedId) basket.add(makeBasketKey(provider.id, selectedId));
+    if (selectedId) basket.toggle(makeBasketKey(provider.id, selectedId));
   };
 
   // When the selected package is already in the basket, PackageDetail swaps