fix: Update GitLab CI/CD pipeline for Python 3.13 and MongoDB

Changes:
- Update PYTHON_VERSION from 3.10 to 3.13
- Update POETRY_VERSION from 1.7.1 to 1.8.0
- Replace PostgreSQL with MongoDB in test services
- Update test environment variables for MongoDB
- Remove Redis service (not used in current implementation)

This fixes the pipeline error:
"The currently activated Python version 3.10.19 is not supported by the project (^3.13)"

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

.gitlab-ci.yml

@@ -8,8 +8,8 @@ stages:
   - docs
 
 variables:
-  POETRY_VERSION: "1.7.1"
-  PYTHON_VERSION: "3.10"
+  POETRY_VERSION: "1.8.0"
+  PYTHON_VERSION: "3.13"
   DOCKER_DRIVER: overlay2
   DOCKER_TLS_CERTDIR: "/certs"
   PIP_CACHE_DIR: "$CI_PROJECT_DIR/.cache/pip"
@@ -65,14 +65,10 @@ test:unit:
   extends: .python-base
   stage: test
   services:
-    - redis:7-alpine
-    - postgres:15-alpine
+    - mongo:7-jammy
   variables:
-    POSTGRES_DB: testdb
-    POSTGRES_USER: test
-    POSTGRES_PASSWORD: test
-    REDIS_URL: redis://redis:6379/0
-    DATABASE_URL: postgresql://test:test@postgres:5432/testdb
+    MONGODB_URL: mongodb://mongo:27017
+    MONGODB_DATABASE: testdb
   script:
     - poetry run pytest tests/unit -v --cov --cov-report=xml --cov-report=term
   coverage: '/(?i)total.*? (100(?:\.0+)?\%|[1-9]?\d(?:\.\d+)?\%)$/'
@@ -93,14 +89,10 @@ test:integration:
   extends: .python-base
   stage: test
   services:
-    - redis:7-alpine
-    - postgres:15-alpine
+    - mongo:7-jammy
   variables:
-    POSTGRES_DB: testdb
-    POSTGRES_USER: test
-    POSTGRES_PASSWORD: test
-    REDIS_URL: redis://redis:6379/0
-    DATABASE_URL: postgresql://test:test@postgres:5432/testdb
+    MONGODB_URL: mongodb://mongo:27017
+    MONGODB_DATABASE: testdb
   script:
     - poetry run pytest tests/integration -v
   only: