fix(web): long-press delay on mobile status-header drag (BUG-641) (#237)

ListView's outer dndzone for status groups was missing `delayTouchStart`,
so any touch on a group header was immediately interpreted as the start
of a group-reorder drag. On mobile this meant trying to scroll the page
by touching a header instead grabbed the header and dragged it with the
finger — the page wouldn't scroll and the user couldn't reach content
below the visible status bands.

Mirror the inner item dndzone's `delayTouchStart: touchDragDelayMs`
(500ms) on the outer group dndzone so the same long-press gesture is
required to start a group reorder. Quick taps (collapse toggle) and
short touch-drags (page scroll) now pass through unmolested; the
existing drag-to-reorder behaviour is preserved behind the long-press,
matching what already works for items inside a group.

The `touchDragDelayMs` constant (line 46) was already in scope and
already used for the inner dndzone, so this is a one-line addition.

Verified manually on iOS at the running server: status headers no
longer hijack scroll; long-press still reorders groups; tap-to-collapse
unaffected.

Verified: web/npm run build clean, go test ./... green.

web/src/lib/components/collections/ListView.svelte

@@ -206,7 +206,15 @@
 			flipDurationMs,
 			type: 'list-group',
 			dropTargetClasses: ['group-drop-target'],
-			morphDisabled: true
+			morphDisabled: true,
+			/* On mobile, touching a group header to scroll the page used to
+			   immediately seize the touch as the start of a group-reorder drag,
+			   so the page wouldn't scroll and the group would fly around with
+			   the finger. Mirror the inner item dndzone's `delayTouchStart`
+			   (BUG-641): a 500ms long-press is required before drag activates,
+			   which matches the existing intra-group item behaviour and lets
+			   ordinary taps/scrolls pass through unmolested. */
+			delayTouchStart: touchDragDelayMs
 		}}
 		onconsider={handleGroupConsider}
 		onfinalize={handleGroupFinalize}