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]/share/location/[id]/LocationViewPage.tsx

@@ -0,0 +1,47 @@
+import { ViewLocationCard } from '@/app/ui/ViewLocationCard';
+import { fetchLocationById, setSeenByTenantAt, validateShareAccess } from '@/app/lib/actions/locationActions';
+import { getUserSettingsByUserId } from '@/app/lib/actions/userSettingsActions';
+import { notFound } from 'next/navigation';
+import { myAuth } from '@/app/lib/auth';
+
+export default async function LocationViewPage({ shareId }: { shareId: string }) {
+    // Validate share access (checks checksum + TTL, extracts locationId)
+    const accessValidation = await validateShareAccess(shareId);
+
+    if (!accessValidation.valid || !accessValidation.locationId) {
+        return (
+            <div className="alert alert-error">
+                <p>{accessValidation.error || 'This content is no longer shared'}</p>
+            </div>
+        );
+    }
+
+    const locationId = accessValidation.locationId;
+
+    // Fetch location
+    const location = await fetchLocationById(locationId);
+
+    if (!location) {
+        return notFound();
+    }
+
+    // Fetch user settings for the location owner
+    const userSettings = await getUserSettingsByUserId(location.userId);
+
+    // Check if the page was accessed by an authenticated user who is the owner
+    const session = await myAuth();
+    const isOwner = session?.user?.id === location.userId;
+
+    // If the page is not visited by the owner, mark it as seen by tenant
+    if (!isOwner) {
+         await setSeenByTenantAt(locationId);
+    }
+
+    return (
+        <ViewLocationCard
+            location={location}
+            userSettings={userSettings}
+            shareId={shareId}
+        />
+    );
+}

web-app/app/[locale]/share/location/[id]/page.tsx

@@ -0,0 +1,14 @@
+import { Suspense } from 'react';
+import LocationViewPage from './LocationViewPage';
+import { Main } from '@/app/ui/Main';
+import { LocationEditFormSkeleton } from '@/app/ui/LocationEditForm';
+
+export default async function Page({ params: { id } }: { params: { id: string } }) {
+    return (
+        <Main>
+            <Suspense fallback={<LocationEditFormSkeleton />}>
+                <LocationViewPage shareId={id} />
+            </Suspense>
+        </Main>
+    );
+}