Initial commit: PESCO NCR system

Complete Non-Conformance Report system replacing the PowerApps/SharePoint
prototype: FastAPI + SQLAlchemy 2 (async) + Alembic + MySQL 8 backend,
React 18 + Vite + TypeScript + MUI frontend, Entra ID auth (MSAL / JWKS,
group-gated), Microsoft Graph delegated Mail.Send notifications (OBO),
six-stage workflow state machine with server-side enforcement, atomic
NCR-YYYY-NNNN numbering, attachments with camera capture, immutable
field-level audit trail, admin reopen, reports + CSV export, WeasyPrint
PDF traveler, Power BI reporting views + read-only DB user, documented
VISUAL ERP job-lookup stub, pytest suite (26 tests), docker-compose
deployment.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

backend/app/schemas/common.py

@@ -0,0 +1,19 @@
+from datetime import datetime, timezone
+from typing import Annotated
+
+from pydantic import BaseModel, ConfigDict, PlainSerializer
+
+
+def _serialize_utc(dt: datetime) -> str:
+    """All DB datetimes are naive UTC; emit RFC3339 with Z so browsers parse
+    them into the user's local timezone."""
+    if dt.tzinfo is None:
+        dt = dt.replace(tzinfo=timezone.utc)
+    return dt.isoformat().replace("+00:00", "Z")
+
+
+UTCDateTime = Annotated[datetime, PlainSerializer(_serialize_utc, return_type=str)]
+
+
+class AppModel(BaseModel):
+    model_config = ConfigDict(from_attributes=True)