fix: prevent platform admin from being auto-enrolled in default school

Two root causes fixed:

1. seed_environment.py: KevlarAI website was 'https://kevlarai.com' (real
   domain) instead of 'https://kevlarai.test'. Also, seed step 8 now patches
   kcar's auth user_metadata to set user_type='platform_admin' on every
   reset+seed, so the fix is self-healing and doesn't require manual DB edits.

2. provisioning_service.py: user_type_map now maps 'platform_admin' to
   ('superadmin', 'superadmin'), so _ensure_membership() is never called for
   platform admin accounts and they are never silently enrolled in the
   default institute.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

modules/database/services/provisioning_service.py

@@ -263,6 +263,7 @@ class ProvisioningService:
             "admin": ("superadmin", "superadmin"),
             "super_admin": ("superadmin", "superadmin"),
             "superadmin": ("superadmin", "superadmin"),
+            "platform_admin": ("superadmin", "superadmin"),
         }
         neo_user_type, worker_type = user_type_map.get(user_type_raw, (user_type_raw or "standard", user_type_raw or "standard"))
 

run/initialization/seed_environment.py

@@ -203,7 +203,7 @@ def seed() -> Dict[str, Any]:
             "name":    KEVLARAI_NAME,
             "urn":     KEVLARAI_URN,
             "status":  "active",
-            "website": "https://kevlarai.com",
+            "website": "https://kevlarai.test",
             "address": {"line1": "1 AI Lane", "city": "London", "postcode": "EC1A 1BB"},
             "metadata": {"headteacher": "Alex Admin", "seeded": True},
         }, on_conflict="id")
@@ -392,6 +392,22 @@ def seed() -> Dict[str, Any]:
         errors.append(f"kcar_admin: {e}")
         logger.error(f"  {e}")
 
+    # Fix kcar's auth user_metadata so user_type is "platform_admin", not "teacher".
+    # Without this, POST /user/init assigns kcar to the default school on first login.
+    try:
+        r = requests.patch(
+            f"{url}/auth/v1/admin/users/{KCAR_ID}",
+            headers=headers,
+            json={"user_metadata": {"user_type": "platform_admin"}},
+        )
+        if r.status_code in (200, 201):
+            logger.info("  kcar → user_type: platform_admin ✓")
+        else:
+            logger.warning(f"  kcar user_metadata patch failed ({r.status_code}): {r.text[:120]}")
+    except Exception as e:
+        errors.append(f"kcar_user_type: {e}")
+        logger.error(f"  {e}")
+
     # ── Summary ───────────────────────────────────────────────────────────────
     results["success"] = len(errors) == 0
     results["errors"]  = errors