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>

housekeeping/README.md

@@ -0,0 +1,27 @@
+# Housekeeping
+
+Database backup and maintenance scripts for the Evidencija Režija application.
+
+## Scripts
+
+- `db-backup--standalone.sh` - Backup database in standalone deployment
+- `db-backup--swarm.sh` - Backup database in Docker Swarm deployment
+- `db-dump--standalone.sh` - Dump database in standalone deployment
+- `db-restore-from-dump--standalone.sh` - Restore from dump in standalone deployment
+- `db-restore-from-backup--swarm.sh` - Restore from backup in Docker Swarm deployment
+
+## Usage
+
+From the monorepo root:
+
+```bash
+npm run backup:standalone --workspace=housekeeping
+npm run backup:swarm --workspace=housekeeping
+```
+
+Or directly from the housekeeping directory:
+
+```bash
+cd housekeeping
+./db-backup--standalone.sh
+```