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.

.gitlab-ci.yml

@@ -60,12 +60,16 @@ release:
     TWINE_USERNAME: gitlab-ci-token
     TWINE_PASSWORD: $CI_JOB_TOKEN
     ENVIRONMENT: test
-  before_script: # common setup for every job
+  before_script:
     - python3.12 -m venv $VIRTUAL_ENV
     - source $VIRTUAL_ENV/bin/activate
     - pip install --upgrade pip
+    # Explicit clean-up commands
     - find "$CI_PROJECT_DIR" -name '__pycache__' -type d -exec rm -rf {} + || true
     - find "$CI_PROJECT_DIR" -name '*.pyc' -type f -delete || true
+    # Fix permissions (if necessary)
+    - chmod -R u+w "$CI_PROJECT_DIR"
+
   script:
     # build and run commands within docker container context
     - docker compose build backend