Adapt CI/CD and endpoint defaults for Sinbad2 production.

Configure GitLab deploy pipeline for this app and switch backend/frontend endpoint defaults from localhost to sinbad2.ujaen.es, including Docker, env files, API client, CORS, and docs.

backend/app/core/config.py

@@ -10,7 +10,7 @@ class Settings(BaseSettings):
     api_prefix: str = ""
     api_key: str = Field(min_length=16)
     database_url: str = "postgresql+psycopg://genexamenes:genexamenes@localhost:5432/genexamenes"
-    allowed_origins: str = "http://localhost:8075"
+    allowed_origins: str = "http://sinbad2.ujaen.es,http://sinbad2.ujaen.es:8075"
     rate_limit_requests: int = Field(default=60, ge=1)
     rate_limit_window_seconds: int = Field(default=60, ge=1)
     max_request_bytes: int = Field(default=1_048_576, ge=1_024)