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/hooks/useInvalidatePlanningViews.ts

@@ -1,8 +1,19 @@
 import { trpc } from "~/lib/trpc/client.js";
 
+/** Invalidates just the 4 timeline queries */
+export function useInvalidateTimeline() {
+  const utils = trpc.useUtils();
+  return () => {
+    void utils.timeline.getEntries.invalidate();
+    void utils.timeline.getEntriesView.invalidate();
+    void utils.timeline.getProjectContext.invalidate();
+    void utils.timeline.getBudgetStatus.invalidate();
+  };
+}
+
+/** Invalidates all 8 planning-related queries (4 timeline + 4 allocation) */
 export function useInvalidatePlanningViews() {
   const utils = trpc.useUtils();
-
   return () => {
     void utils.allocation.list.invalidate();
     void (