Fix TypeScript config for .ts import extensions

- allowImportingTsExtensions: true + noEmit: true in tsconfig
- build script runs tsc --noEmit (type-check only)
- Dockerfile simplified to single stage using tsx at runtime
  (no tsc compilation needed; tsx handles .ts imports natively)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Dockerfile

@@ -1,5 +1,4 @@
-# Build stage
-FROM node:22-alpine AS build
+FROM node:22-alpine
 
 # Install native build tools for bcrypt
 RUN apk add --no-cache python3 make g++
@@ -11,24 +10,10 @@ RUN npm ci
 
 COPY tsconfig.json ./
 COPY src ./src
-
-RUN npm run build
-
-# Runtime stage
-FROM node:22-alpine AS runtime
-
-RUN apk add --no-cache python3 make g++
-
-WORKDIR /app
-
-COPY package*.json ./
-RUN npm ci --omit=dev
-
-COPY --from=build /app/dist ./dist
 COPY public ./public
 
 RUN mkdir -p /app/data/uploads
 
 EXPOSE 3000
 
-CMD ["node", "dist/index.js"]
+CMD ["node", "--import", "tsx", "src/index.ts"]