audit: Tier 1/3/4/5/7 batch — SSE, gates, dedup, URL escape, FK constraints

Tier 1.6: S3Backend.put now sets ServerSideEncryption=AES256 — closes
the cleartext-at-rest gap for signed contracts, GDPR exports, pg_dumps.

Tier 3.7: New safeUrl() helper in lib/email/shell.ts. Scheme allow-list
(http/https/mailto/tel/relative only — javascript:/data:/vbscript:/file:
rewritten to about:blank) + HTML-attribute escape. Retrofitted across
all 7 transactional templates (crm-invite, portal-auth, document-signing,
notification-digest, residential-inquiry, admin-email-change).

Tier 4.2: /api/v1/alerts GET now gated on admin.view_audit_log.

Tier 4.3: Documenso webhook handler emits captureErrorEvent on catch.
Admin/errors no longer silent on webhook crashes.

Tier 4.6: Inquiry-funnel email dedup is now case-insensitive
(LOWER(value)) and stores normalized email on insert. Capital-letter
resubmissions no longer spawn duplicate client+yacht+interest rows.

Tier 5.6 + data-model H1: migration 0056 adds FK
user_permission_overrides.user_id → user(id) cascade, same for
user_port_roles.userId, plus partial unique index on
user_email_changes pending rows.

Tier 7.6: @types/node bumped from ^25 to ^20.19.0 — matches the runtime.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/api/public/interests/route.ts

@@ -84,11 +84,18 @@ export async function POST(req: NextRequest) {
 
     // ─── Transactional trio creation ────────────────────────────────────────
     const result = await withTransaction(async (tx) => {
-      // 1. Find or create client by email (case-sensitive contact match, same
-      //    behavior as before the refactor).
+      // 1. Find or create client by email. The inquiry-funnel audit
+      //    flagged that the previous exact match was case-sensitive —
+      //    capital-letter resubmissions spawned duplicate client+yacht+
+      //    interest rows. Match LOWER(value) instead so foo@x.com and
+      //    Foo@X.COM dedupe to the same client.
       let clientId: string;
+      const normalizedEmail = data.email.trim().toLowerCase();
       const existingContact = await tx.query.clientContacts.findFirst({
-        where: and(eq(clientContacts.channel, 'email'), eq(clientContacts.value, data.email)),
+        where: and(
+          eq(clientContacts.channel, 'email'),
+          sql`LOWER(${clientContacts.value}) = ${normalizedEmail}`,
+        ),
       });
       if (existingContact) {
         const existingClient = await tx.query.clients.findFirst({
@@ -320,7 +327,9 @@ async function createClientInTx(
   await tx.insert(clientContacts).values({
     clientId,
     channel: 'email',
-    value: data.email,
+    // Store lowercased so the case-insensitive dedup match above always
+    // hits on subsequent submissions.
+    value: data.email.trim().toLowerCase(),
     isPrimary: true,
   });