feat(expenses): Add delete expense endpoint and functionality

Implements the ability to delete an expense, including its associated items and shares. Also refactors the expense update logic to correctly handle share updates and adds the corresponding API endpoint and mock DB function.

Dockerfile

@@ -1,15 +0,0 @@
-# Stage 1: Build Frontend
-FROM node:18-alpine as build
-WORKDIR /app
-COPY package*.json ./
-RUN npm install
-COPY . .
-RUN npm run build
-
-# Stage 2: Serve with Nginx
-FROM nginx:alpine
-COPY --from=build /app/dist /usr/share/nginx/html
-# Copy the nginx configuration file (using the .txt extension as provided in source)
-COPY nginx.txt /etc/nginx/nginx.conf
-EXPOSE 80
-CMD ["nginx", "-g", "daemon off;"]