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/[locale]/home/account/page.tsx

@@ -0,0 +1,30 @@
+import { FC } from 'react';
+import { Main } from '@/app/ui/Main';
+import Link from 'next/link';
+import SettingsIcon from "@mui/icons-material/Settings";
+import HomeIcon from "@mui/icons-material/Home";
+import AccountCircle from "@mui/icons-material/AccountCircle";
+import { getTranslations, getLocale } from 'next-intl/server';
+import { LogoutButton } from './LogoutButton';
+
+const Page: FC = async () => {
+    const t = await getTranslations('account-page');
+    const locale = await getLocale();
+
+    return (
+        <Main>
+            <div className="flex flex-col items-center">
+                <div className="card card-compact card-bordered min-w-[20em] max-w-[90em] bg-base-100 shadow-s my-1">
+                    <div className="card-body">
+                        <h2 className="card-title"><AccountCircle /> {t('title')}</h2>
+                        <Link href={`/${locale}/home`} className='btn btn-neutral'><HomeIcon className='text-white'/> {t('goto-home-button-label')}</Link>
+                        <Link href={`/${locale}/home/account/settings`} className='btn btn-neutral'><SettingsIcon className='text-blue-400' /> {t('goto-settings-button-label')}</Link>
+                        <LogoutButton />
+                    </div>
+                </div>
+            </div>
+        </Main>
+    );
+};
+
+export default Page;