Pinscope open-source core

Agentic schematic validation: datasheet extraction via Claude Console
Skills, netlist/BOM design graph, per-IC direct datasheet review with
page citations, capacitor derating, Next.js report UI.

Extracted from the Pinscope cloud codebase. Auth and billing live in the
private gateway repo behind stable seams (billing_hook.py, adapter files
listed in CLAUDE.md).

backend/services/admin_settings.py

@@ -0,0 +1,48 @@
+"""Global admin settings, persisted via StorageBackend.
+
+Settings are stored at ``admin/settings.json`` in storage (GCS or local
+``data/``).  The module mirrors the pattern in ``limits.py``.
+"""
+
+from __future__ import annotations
+
+from packaging.version import Version
+
+from backend.services.storage import StorageBackend
+
+_SETTINGS_KEY = "admin/settings.json"
+
+_DEFAULTS: dict[str, str] = {
+    "min_model_version": "0.0.0",  # no threshold by default
+}
+
+
+def get_admin_settings(storage: StorageBackend) -> dict:
+    """Return the full admin settings dict, with defaults."""
+    if storage.exists(_SETTINGS_KEY):
+        data = storage.read_json(_SETTINGS_KEY)
+        return {**_DEFAULTS, **data}
+    return dict(_DEFAULTS)
+
+
+def get_min_model_version(storage: StorageBackend) -> str:
+    """Return the min_model_version threshold."""
+    return get_admin_settings(storage).get("min_model_version", "0.0.0")
+
+
+def set_min_model_version(storage: StorageBackend, version: str) -> None:
+    """Set the min_model_version threshold.  Validates semver format."""
+    Version(version)  # raises InvalidVersion if bad
+    data = get_admin_settings(storage)
+    data["min_model_version"] = version
+    storage.write_json(_SETTINGS_KEY, data)
+
+
+def version_is_stale(component_version: str, min_version: str) -> bool:
+    """Return True if *component_version* < *min_version* (semver)."""
+    if min_version == "0.0.0":
+        return False
+    try:
+        return Version(component_version) < Version(min_version)
+    except Exception:
+        return True  # unparseable → treat as stale