feat(etl-cache): add EtlCacheSettings resolved from config

surfsense_backend/app/etl_pipeline/cache/settings.py

@@ -0,0 +1,33 @@
+"""Cache configuration resolved from the central ``Config``."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class EtlCacheSettings:
+    enabled: bool
+    parser_version: int
+    ttl_days: int
+    max_total_bytes: int
+    eviction_batch: int
+    # None for any storage_* field means: reuse the main file_storage backend.
+    storage_backend: str | None
+    storage_container: str | None
+    storage_local_root: str | None
+
+
+def load_etl_cache_settings() -> EtlCacheSettings:
+    from app.config import config
+
+    return EtlCacheSettings(
+        enabled=config.ETL_CACHE_ENABLED,
+        parser_version=config.ETL_CACHE_PARSER_VERSION,
+        ttl_days=config.ETL_CACHE_TTL_DAYS,
+        max_total_bytes=config.ETL_CACHE_MAX_TOTAL_MB * 1024 * 1024,
+        eviction_batch=config.ETL_CACHE_EVICTION_BATCH,
+        storage_backend=config.ETL_CACHE_STORAGE_BACKEND or None,
+        storage_container=config.ETL_CACHE_STORAGE_CONTAINER or None,
+        storage_local_root=config.ETL_CACHE_STORAGE_LOCAL_PATH or None,
+    )