Fix data-corruption on PK-less table; scrub real emails from examples

Critical: NocoDB v2 PATCH /records with no primary key updates EVERY row, so a
table missing its Id column made each redeem rewrite all tickets' counts.
- nocodb update() now refuses to PATCH a record with no Id (fail-safe).
- Document that the tickets/audit tables must have an Id PK; note how to add it.
- Replace the real donor email/name used in the /test persona and the
  FluentForms guide with fake placeholders (donor@example.test / <a-real-donor-email>).

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

backend/src/routes/test.ts

@@ -36,13 +36,14 @@ const PERSONAS: Persona[] = [
       "5 tickets (2 under-4 free), car parking, 3 ice bags. Check-in a few at a time to test QR reuse; then Ice mode.",
   },
   {
-    key: "donor",
-    name: "Adam Stevens (real donor)",
-    email: "adam21stevens@gmail.com",
+    key: "donor2",
+    name: "Donor Dan",
+    email: "donor@example.test",
     ages: { "Ages 26-45": 2 },
     rvParking: true,
     isDonor: true,
-    blurb: "2 tickets, RV parking. Banquet mode → shows real donation total ($801).",
+    blurb:
+      "2 tickets, RV parking, donor-flagged. Banquet mode: this test email has no real donations, so use Banquet's manual email lookup with a real donor's address to see totals.",
   },
   {
     key: "ice",