Рефакторинг инфраструктуры и конфигурации проекта

- Перенесена структура Django-конфига в src/core и src/settings

- Унифицирована Docker-сборка и docker-compose для dev/prod

- Добавлены startup-checks (DB/Redis) и обновлены env-шаблоны

- Расширена OpenAPI-документация и ответы API

- Удалены устаревшие deploy/requirements/служебные скрипты

- Обновлены CI/CD, README и тесты

src/apps/core/startup_checks.py

@@ -0,0 +1,91 @@
+"""
+Startup dependency checks for DB and Redis.
+
+Fail-fast checks used by long-running entrypoints (web/celery) to avoid
+silent hangs on connection issues.
+"""
+
+from __future__ import annotations
+
+import sys
+from urllib.parse import urlparse
+
+import psycopg2
+import redis
+from django.conf import settings
+
+
+def _log(message: str) -> None:
+    """Log to stderr to be visible early in startup."""
+    print(message, file=sys.stderr)
+
+
+def _check_db(timeout_seconds: int) -> tuple[bool, str]:
+    db = settings.DATABASES["default"]
+    params = {
+        "dbname": db.get("NAME"),
+        "user": db.get("USER"),
+        "password": db.get("PASSWORD"),
+        "host": db.get("HOST"),
+        "port": db.get("PORT"),
+        "connect_timeout": timeout_seconds,
+    }
+
+    options = db.get("OPTIONS", {})
+    if options.get("sslmode"):
+        params["sslmode"] = options["sslmode"]
+
+    conn = None
+    try:
+        conn = psycopg2.connect(**params)
+        with conn.cursor() as cursor:
+            cursor.execute("SELECT 1")
+            cursor.fetchone()
+        return True, "OK"
+    except Exception as exc:  # noqa: BLE001
+        target = f"{params['host']}:{params['port']}/{params['dbname']}"
+        return False, f"{target} ({exc})"
+    finally:
+        if conn is not None:
+            conn.close()
+
+
+def _check_redis(timeout_seconds: int) -> tuple[bool, str]:
+    redis_url = settings.CACHES["default"]["LOCATION"]
+    try:
+        client = redis.Redis.from_url(
+            redis_url,
+            socket_connect_timeout=timeout_seconds,
+            socket_timeout=timeout_seconds,
+        )
+        client.ping()
+        return True, "OK"
+    except Exception as exc:  # noqa: BLE001
+        parsed = urlparse(redis_url)
+        target = f"{parsed.hostname}:{parsed.port}{parsed.path or ''}"
+        return False, f"{target} ({exc})"
+
+
+def run_startup_checks(*, component: str = "app") -> None:
+    """Run startup checks and exit process on failure."""
+    if not getattr(settings, "STARTUP_CHECKS_ENABLED", True):
+        return
+
+    db_timeout = int(getattr(settings, "STARTUP_DB_TIMEOUT_SECONDS", 3))
+    redis_timeout = int(getattr(settings, "STARTUP_REDIS_TIMEOUT_SECONDS", 3))
+
+    db_ok, db_message = _check_db(db_timeout)
+    if not db_ok:
+        _log(
+            f"[startup:{component}] DB check failed "
+            f"(timeout={db_timeout}s): {db_message}"
+        )
+        raise SystemExit(1)
+
+    redis_ok, redis_message = _check_redis(redis_timeout)
+    if not redis_ok:
+        _log(
+            f"[startup:{component}] Redis check failed "
+            f"(timeout={redis_timeout}s): {redis_message}"
+        )
+        raise SystemExit(1)