feat(16-01): thread signers state through DocumentPageClient

- Server page passes doc.signers as initialSigners to DocumentPageClient
- DocumentPageClient adds signers + unassignedFieldIds state (initialized from server)
- Props threaded to PdfViewerWrapper (signers, unassignedFieldIds) and PreparePanel (signers, onSignersChange, unassignedFieldIds, onUnassignedFieldIdsChange)
- PreparePanel interface extended to accept new optional multi-signer props

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

teressa-copeland-homes/src/app/portal/(protected)/documents/[docId]/_components/DocumentPageClient.tsx

@@ -2,6 +2,7 @@
 import { useState, useCallback } from 'react';
 import { PdfViewerWrapper } from './PdfViewerWrapper';
 import { PreparePanel } from './PreparePanel';
+import type { DocumentSigner } from '@/lib/db/schema';
 
 interface DocumentPageClientProps {
   docId: string;
@@ -11,6 +12,7 @@ interface DocumentPageClientProps {
   agentDownloadUrl?: string | null;
   signedAt?: Date | null;
   clientPropertyAddress?: string | null;
+  initialSigners: DocumentSigner[];
 }
 
 export function DocumentPageClient({
@@ -21,11 +23,14 @@ export function DocumentPageClient({
   agentDownloadUrl,
   signedAt,
   clientPropertyAddress,
+  initialSigners,
 }: DocumentPageClientProps) {
   const [previewToken, setPreviewToken] = useState<string | null>(null);
   const [selectedFieldId, setSelectedFieldId] = useState<string | null>(null);
   const [textFillData, setTextFillData] = useState<Record<string, string>>({});
   const [aiPlacementKey, setAiPlacementKey] = useState(0);
+  const [signers, setSigners] = useState<DocumentSigner[]>(initialSigners);
+  const [unassignedFieldIds, setUnassignedFieldIds] = useState<Set<string>>(new Set());
 
   const handleFieldsChanged = useCallback(() => {
     setPreviewToken(null);
@@ -71,6 +76,8 @@ export function DocumentPageClient({
           onFieldSelect={setSelectedFieldId}
           onFieldValueChange={handleFieldValueChange}
           aiPlacementKey={aiPlacementKey}
+          signers={signers}
+          unassignedFieldIds={unassignedFieldIds}
         />
       </div>
       <div className="lg:col-span-1 lg:sticky lg:top-6 lg:self-start lg:max-h-[calc(100vh-6rem)] lg:overflow-y-auto">
@@ -88,6 +95,10 @@ export function DocumentPageClient({
           selectedFieldId={selectedFieldId}
           onQuickFill={handleQuickFill}
           onAiAutoPlace={handleAiAutoPlace}
+          signers={signers}
+          onSignersChange={setSigners}
+          unassignedFieldIds={unassignedFieldIds}
+          onUnassignedFieldIdsChange={setUnassignedFieldIds}
         />
       </div>
     </div>

teressa-copeland-homes/src/app/portal/(protected)/documents/[docId]/_components/PreparePanel.tsx

@@ -2,6 +2,7 @@
 import { useState, useEffect } from 'react';
 import { useRouter } from 'next/navigation';
 import dynamic from 'next/dynamic';
+import type { DocumentSigner } from '@/lib/db/schema';
 
 // PreviewModal imports react-pdf which calls new DOMMatrix() at module level —
 // must be loaded client-only to avoid SSR crash, same pattern as PdfViewer.
@@ -21,6 +22,11 @@ interface PreparePanelProps {
   selectedFieldId: string | null;
   onQuickFill: (fieldId: string, value: string) => void;
   onAiAutoPlace: () => Promise<void>;
+  // Multi-signer props — wired in Phase 16, consumed in Wave 2
+  signers?: DocumentSigner[];
+  onSignersChange?: (signers: DocumentSigner[]) => void;
+  unassignedFieldIds?: Set<string>;
+  onUnassignedFieldIdsChange?: (ids: Set<string>) => void;
 }
 
 function parseEmails(raw: string | undefined): string[] {

teressa-copeland-homes/src/app/portal/(protected)/documents/[docId]/page.tsx

@@ -60,6 +60,7 @@ export default async function DocumentPage({
         agentDownloadUrl={agentDownloadUrl}
         signedAt={doc.signedAt ?? null}
         clientPropertyAddress={docClient?.propertyAddress ?? null}
+        initialSigners={doc.signers ?? []}
       />
     </div>
   );