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.

server/Dockerfile

@@ -1,13 +0,0 @@
-FROM node:18-alpine
-WORKDIR /app
-
-# Set production environment
-ENV NODE_ENV=production
-
-COPY package*.json ./
-RUN npm install --production
-
-COPY . .
-
-EXPOSE 3001
-CMD ["node", "server.js"]