Add job processing system with streaming endpoint

Introduced a `processing` router to handle job streaming using server-sent events. Added `Jobs` and `JobStatus` models for managing job-related data, along with database creation logic. Updated the `sample` router to create new job entries during experiment creation.

backend/Dockerfile

@@ -36,6 +36,8 @@ RUN pip install --no-cache-dir -r requirements.txt
 # Copy the rest of the application code
 COPY . /app
 
+RUN mkdir -p /app/backend/ssl
+
 # Expose the application port
 EXPOSE 8000