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>

packages/api/src/router/staffing-suggestions-read.ts

@@ -1,6 +1,6 @@
 import { rankResources } from "@capakraken/staffing";
 import { listAssignmentBookings } from "@capakraken/application";
-import { PermissionKey, type WeekdayAvailability } from "@capakraken/shared";
+import { PermissionKey, toIsoDateOrNull, type WeekdayAvailability } from "@capakraken/shared";
 import { z } from "zod";
 import { findUniqueOrThrow } from "../db/helpers.js";
 import { loadResourceDailyAvailabilityContexts } from "../lib/resource-capacity.js";
@@ -17,10 +17,6 @@ import {
 } from "./staffing-shared.js";
 import { buildResourceCapacitySummary } from "./staffing-capacity-summary.js";
 
-function fmtDate(value: Date | null | undefined): string | null {
-  return value ? value.toISOString().slice(0, 10) : null;
-}
-
 type StaffingSuggestionInput = {
   requiredSkills: string[];
   preferredSkills?: string[] | undefined;
@@ -415,7 +411,7 @@ export const staffingSuggestionsReadProcedures = {
       });
       return {
         project: `${project.name} (${project.shortCode})`,
-        period: `${fmtDate(startDate)} to ${fmtDate(endDate)}`,
+        period: `${toIsoDateOrNull(startDate)} to ${toIsoDateOrNull(endDate)}`,
         suggestions: suggestions
           .filter((suggestion) => {
             if (!normalizedRoleFilter) {