Fix client-side cache staleness after proof of payment upload

Added cache revalidation to ensure ViewLocationCard reflects uploaded
proof of payment when navigating back from ViewBillCard:

- Server-side: Added revalidatePath() to upload actions in billActions
  and locationActions to invalidate Next.js server cache
- Client-side: Added router.refresh() calls in ViewBillCard and
  ViewLocationCard to refresh client router cache after successful upload

This maintains the current UX (no redirect on upload) while ensuring
fresh data is displayed on navigation.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/lib/actions/billActions.ts

@@ -2,14 +2,14 @@
 
 import { z } from 'zod';
 import { getDbClient } from '../dbClient';
-import { Bill, BilledTo, FileAttachment, BillingLocation, YearMonth } from '../db-types';
+import { Bill, BilledTo, FileAttachment, BillingLocation } from '../db-types';
 import { ObjectId } from 'mongodb';
 import { withUser } from '@/app/lib/auth';
 import { AuthenticatedUser } from '../types/next-auth';
-import { gotoHome, gotoHomeWithMessage } from './navigationActions';
+import { gotoHomeWithMessage } from './navigationActions';
 import { getTranslations, getLocale } from "next-intl/server";
 import { IntlTemplateFn } from '@/app/i18n';
-import { unstable_noStore } from 'next/cache';
+import { unstable_noStore, revalidatePath } from 'next/cache';
 
 export type State = {
     errors?: {
@@ -116,6 +116,8 @@ const serializeAttachment = async (billAttachment: File | null): Promise<FileAtt
  */
 export const updateOrAddBill = withUser(async (user: AuthenticatedUser, locationId: string, billId: string | undefined, billYear: number | undefined, billMonth: number | undefined, prevState: State, formData: FormData) => {
 
+    unstable_noStore();
+
     const { id: userId } = user;
 
     const t = await getTranslations("bill-edit-form.validation");
@@ -351,6 +353,7 @@ export const fetchBillByUserAndId = withUser(async (user:AuthenticatedUser, loca
 
 export const fetchBillById = async (locationID: string, billID: string, includeAttachmentBinary: boolean = false) => {
 
+    unstable_noStore();
 
     const dbClient = await getDbClient();
 
@@ -387,6 +390,8 @@ export const fetchBillById = async (locationID: string, billID: string, includeA
 
 export const deleteBillById = withUser(async (user: AuthenticatedUser, locationID: string, billID: string, year: number, month: number, _prevState: any, formData?: FormData) => {
 
+    unstable_noStore();
+
     const { id: userId } = user;
 
     const dbClient = await getDbClient();
@@ -488,6 +493,7 @@ export const deleteBillById = withUser(async (user: AuthenticatedUser, locationI
  * @returns Promise with success status
  */
 export const uploadProofOfPayment = async (locationID: string, billID: string, formData: FormData): Promise<{ success: boolean; error?: string }> => {
+
     unstable_noStore();
 
     try {
@@ -503,7 +509,7 @@ export const uploadProofOfPayment = async (locationID: string, billID: string, f
         }
 
         // Validate file type
-        if (attachmentFile && attachmentFile.size > 0 && attachmentFile.type !== 'application/pdf') {
+        if (file && file.size > 0 && file.type !== 'application/pdf') {
             return { success: false, error: 'Only PDF files are accepted' };
         }
 
@@ -564,6 +570,9 @@ export const uploadProofOfPayment = async (locationID: string, billID: string, f
             ]
         });
 
+        // Invalidate the location view cache
+        revalidatePath(`/share/location/${locationID}`, 'page');
+
         return { success: true };
     } catch (error: any) {
         console.error('Error uploading proof of payment for a bill:', error);