refactor: convert repository to monorepo with npm workspaces

Restructured the repository into a monorepo to better organize application code
and maintenance scripts.

## Workspace Structure
- web-app: Next.js application (all app code moved from root)
- housekeeping: Database backup and maintenance scripts

## Key Changes
- Moved all application code to web-app/ using git mv
- Moved database scripts to housekeeping/ workspace
- Updated Dockerfile for monorepo build process
- Updated docker-compose files (volume paths: ./web-app/etc/hosts/)
- Updated .gitignore for workspace-level node_modules
- Updated documentation (README.md, CLAUDE.md, CHANGELOG.md)

## Migration Impact
- Root package.json now manages workspaces
- Build commands delegate to web-app workspace
- All file history preserved via git mv
- Docker build process updated for workspace structure

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

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

web-app/app/lib/actions/printActions.ts

@@ -0,0 +1,81 @@
+'use server';
+
+import { getDbClient } from '../dbClient';
+import { BillingLocation } from '../db-types';
+import { AuthenticatedUser } from '../types/next-auth';
+import { withUser } from '../auth';
+import { unstable_noStore as noStore } from 'next/cache';
+
+export interface PrintBarcodeData {
+  locationName: string;
+  billName: string;
+  /**
+   * LEGACY SUPPORT ... untill all bills have been migrated 
+   * @deprecated Use `hub3aText` instead.
+  */
+  barcodeImage?: string;
+  hub3aText?: string;
+  payedAmount?: number | null;
+}
+
+/**
+ * Fetches all bills with barcode images for a specific month for printing
+ * @param year - Year to fetch data for
+ * @param month - Month to fetch data for (1-12)
+ * @returns Array of barcode data for printing
+ */
+export const fetchBarcodeDataForPrint = withUser(async (user: AuthenticatedUser, year: number, month: number): Promise<PrintBarcodeData[]> => {
+    noStore();
+    
+    const { id: userId } = user;
+    const dbClient = await getDbClient();
+
+    const yearMonth = `${year}-${month.toString().padStart(2, '0')}`;
+
+    // Fetch all locations for the specific month
+    const locations = await dbClient.collection<BillingLocation>("lokacije")
+        .find({
+            userId, // ensure data belongs to authenticated user
+            "yearMonth.year": year,
+            "yearMonth.month": month
+        }, {
+            // project only necessary fields
+            projection: {
+                name: 1,
+                bills: 1,
+                barcodeImage: 1,
+                hub3aText: 1,
+                payedAmount: 1,
+                paid: 1
+            }
+        })
+        .toArray();
+
+    // Extract and flatten barcode data
+    const printData: PrintBarcodeData[] = [];
+
+    for (const location of locations) {
+        for (const bill of location.bills) {
+            // Only include bills that have barcode images and are NOT PAID
+            if ( ( bill.hub3aText && bill.hub3aText.trim() !== "" && !bill.paid) ) {
+                printData.push({
+                    locationName: location.name,
+                    billName: bill.name,
+                    barcodeImage: bill.barcodeImage, // LEGACY SUPPORT ... untill all bills have been migrated
+                    hub3aText: bill.hub3aText,
+                    payedAmount: bill.payedAmount
+                });
+            }
+        }
+    }
+
+    // Sort by location name, then by bill name for consistent ordering
+    printData.sort((a, b) => {
+        if (a.locationName !== b.locationName) {
+            return a.locationName.localeCompare(b.locationName);
+        }
+        return a.billName.localeCompare(b.billName);
+    });
+
+    return printData;
+});