feat(timeline): add pulse animation for in-flight drag mutations

Allocation bars that have active optimistic overrides (post-drag,
awaiting server confirmation) now pulse subtly via animate-pulse.
The pending set is derived from the existing optimisticAllocations
map keys, requiring no additional state.

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

apps/web/src/lib/format.ts

@@ -1,3 +1,16 @@
+/**
+ * Format a Date for an HTML <input type="date"> value (yyyy-mm-dd, local timezone).
+ * Returns "" for null/undefined.
+ */
+export function toDateInputValue(date: Date | string | null | undefined): string {
+  if (!date) return "";
+  const d = typeof date === "string" ? new Date(date) : date;
+  const y = d.getFullYear();
+  const m = String(d.getMonth() + 1).padStart(2, "0");
+  const day = String(d.getDate()).padStart(2, "0");
+  return `${y}-${m}-${day}`;
+}
+
 /**
  * Format a date as dd/mm/yyyy for display in the UI.
  * Input date inputs (type="date") still use yyyy-mm-dd — this is for rendered text only.