refactor: consolidate duplicated code across web and API packages

- Extract shared render helpers (vacation blocks, range overlay, overbooking blink) into renderHelpers.tsx
- Centralize status badge styles and vacation color maps into status-styles.ts
- Extract dragMath.ts utility from useTimelineDrag for reuse
- Split useInvalidatePlanningViews into useInvalidateTimeline (4 queries) + useInvalidatePlanningViews (8 queries)
- Adopt findUniqueOrThrow() and Prisma select constants across API routers
- Add shared fmtEur() helper for API-side money formatting
- Wrap TimelineResourcePanel and TimelineProjectPanel with React.memo
- Fix pre-existing TS2589 deep type errors in TeamCalendar and VacationModal
- 38 files changed, reducing ~400 lines of duplicated code

Co-Authored-By: claude-flow <ruv@ruv.net>

apps/web/src/components/dashboard/widgets/ProjectTableWidget.tsx

@@ -4,6 +4,7 @@ import { useState } from "react";
 import Link from "next/link";
 import { trpc } from "~/lib/trpc/client.js";
 import type { WidgetProps } from "~/components/dashboard/widget-registry.js";
+import { formatCents, formatMoney } from "~/lib/format.js";
 import { ProjectStatus } from "@planarchy/shared/types";
 import { InfoTooltip } from "~/components/ui/InfoTooltip.js";
 import { PROJECT_STATUS_BADGE as STATUS_COLORS } from "~/lib/status-styles.js";
@@ -271,7 +272,7 @@ export function ProjectTableWidget({ config, onConfigChange }: WidgetProps) {
                     </span>
                   </td>
                   <td className="px-3 py-2 text-right text-gray-700 dark:text-gray-200">
-                    {(p.totalCostCents / 100).toLocaleString("de-DE", { minimumFractionDigits: 2 })} €
+                    {formatCents(p.totalCostCents)} €
                   </td>
                   <td className="px-3 py-2 text-right text-gray-700 dark:text-gray-200">
                     {p.totalPersonDays}d
@@ -280,7 +281,7 @@ export function ProjectTableWidget({ config, onConfigChange }: WidgetProps) {
                     {p.budgetCents > 0 ? (
                       <div className="flex items-center justify-end gap-1.5">
                         <span className="text-gray-700 dark:text-gray-200">
-                          {(p.budgetCents / 100).toLocaleString("de-DE", { minimumFractionDigits: 0 })} €
+                          {formatMoney(p.budgetCents)}
                         </span>
                         <span
                           className={`inline-block w-2 h-2 rounded-full flex-shrink-0 ${overBudget ? "bg-red-500" : util >= 80 ? "bg-amber-500" : "bg-green-500"}`}