Refactor contact handling across backend and frontend

Replaced usage of "ContactPerson" with "Contact" for consistency across the codebase. Updated related component props, state variables, API calls, and database queries to align with the new model. Also enhanced backend functionality with stricter validations and added support for handling active pgroups in contact management.

backend/main.py

@@ -6,8 +6,6 @@ from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
 from app import ssl_heidi
 from app.routers import (
-    address,
-    contact,
     proposal,
     dewar,
     shipment,
@@ -157,8 +155,6 @@ def on_startup():
 # Include routers with correct configuration
 app.include_router(protected_router, prefix="/protected", tags=["protected"])
 app.include_router(auth.router, prefix="/auth", tags=["auth"])
-app.include_router(contact.router, prefix="/contacts", tags=["contacts"])
-app.include_router(address.protected_router, prefix="/addresses", tags=["addresses"])
 app.include_router(proposal.router, prefix="/proposals", tags=["proposals"])
 app.include_router(dewar.router, prefix="/dewars", tags=["dewars"])
 app.include_router(shipment.router, prefix="/shipments", tags=["shipments"])