fix(auth): harden admin gate, X-Port-Id, portal JWT, saved-views

- Add server-side `<admin>/layout.tsx` that redirects non-super-admins to
  `/[portSlug]/dashboard`. Closes the gap where any authed user could
  guess the URL and reach Users / Roles / Audit Log / Backup.
- `withAuth` super-admin branch now 404s when the requested portId does
  not match a real port row, preventing a compromised super-admin
  session from operating against a fabricated portId.
- Portal JWTs now carry `aud: 'portal'` + `iss: 'pn-crm'` claims and
  `verifyPortalToken` requires both, so a portal token can no longer be
  replayed against the CRM session path or vice versa. In-flight tokens
  (≤24h) will be invalidated once on deploy.
- `saved-views/[id]` PATCH and DELETE now do an explicit ownership
  check before the service call, returning 403 instead of relying on
  the service's internal userId filter.

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

src/app/api/v1/saved-views/[id]/route.ts

@@ -1,14 +1,37 @@
+import { and, eq } from 'drizzle-orm';
 import { NextResponse } from 'next/server';
 
 import { withAuth } from '@/lib/api/helpers';
 import { parseBody } from '@/lib/api/route-helpers';
+import { db } from '@/lib/db';
+import { savedViews } from '@/lib/db/schema';
 import { errorResponse } from '@/lib/errors';
 import { savedViewsService } from '@/lib/services/saved-views.service';
 import { updateSavedViewSchema } from '@/lib/validators/saved-views';
 
+/** Resolves the view and enforces ownership before mutating. */
+async function assertViewOwner(
+  id: string,
+  portId: string,
+  userId: string,
+): Promise<NextResponse | null> {
+  const view = await db.query.savedViews.findFirst({
+    where: and(eq(savedViews.id, id), eq(savedViews.portId, portId)),
+  });
+  if (!view) {
+    return NextResponse.json({ error: 'Not found' }, { status: 404 });
+  }
+  if (view.userId !== userId) {
+    return NextResponse.json({ error: 'Forbidden' }, { status: 403 });
+  }
+  return null;
+}
+
 export const PATCH = withAuth(async (req, ctx, params) => {
   try {
     const id = params.id ?? '';
+    const denied = await assertViewOwner(id, ctx.portId, ctx.userId);
+    if (denied) return denied;
     const body = await parseBody(req, updateSavedViewSchema);
     const view = await savedViewsService.update(ctx.portId, ctx.userId, id, body);
     return NextResponse.json({ data: view });
@@ -20,6 +43,8 @@ export const PATCH = withAuth(async (req, ctx, params) => {
 export const DELETE = withAuth(async (_req, ctx, params) => {
   try {
     const id = params.id ?? '';
+    const denied = await assertViewOwner(id, ctx.portId, ctx.userId);
+    if (denied) return denied;
     await savedViewsService.delete(ctx.portId, ctx.userId, id);
     return NextResponse.json({ data: null }, { status: 200 });
   } catch (error) {