New Dockerfile, still dummy app, testing minimal req file. v3

Dockerfile

@@ -4,7 +4,7 @@ FROM python:3.10-slim
 WORKDIR /app
 
 # Copy requirements first to leverage Docker cache
-COPY _requirements.txt .
+COPY requirements.txt .
 
 # Install dependencies
 RUN pip install --no-cache-dir -r requirements.txt