feat(eoi): in-app pathway fills the same source PDF as Documenso

When the in-app pathway is used for EOI templates, we now load the same
source PDF that the Documenso template uploads and fill its AcroForm
fields with values from EoiContext via pdf-lib. Field names mirror the
Documenso template's formValues keys exactly (Name, Email, Address,
Yacht Name, Length, Width, Draft, Berth Number + Lease_10 / Purchase
checkboxes), so both pathways produce equivalent legal documents — only
the renderer differs.

The form is left interactive (not flattened) so a recipient can still
adjust values before signing. Non-EOI templates (welcome letters,
acknowledgments, etc.) keep using the existing HTML→pdfme path.

Adds:
- pdf-lib direct dep
- src/lib/pdf/fill-eoi-form.ts — load + fill helpers, EOI_TEMPLATE_PDF_PATH
  env override
- assets/ + README documenting the expected source PDF
- next.config outputFileTracingIncludes so the asset is bundled in the
  standalone build

Tests: 8 new (4 fill-form unit + 2 source-PDF route + 2 fallback);
645/645 green.

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

tests/integration/document-templates-generate-and-sign.test.ts

@@ -42,6 +42,14 @@ vi.mock('@/lib/pdf/generate', () => ({
   generatePdf: vi.fn().mockResolvedValue(new Uint8Array(Buffer.from('fake-pdf'))),
 }));
 
+vi.mock('@/lib/pdf/fill-eoi-form', () => ({
+  generateEoiPdfFromTemplate: vi
+    .fn()
+    .mockResolvedValue(new Uint8Array(Buffer.from('fake-eoi-pdf'))),
+  loadEoiTemplatePdf: vi.fn(),
+  fillEoiFormFields: vi.fn(),
+}));
+
 vi.mock('@/lib/audit', () => ({
   createAuditLog: vi.fn().mockResolvedValue(undefined),
 }));
@@ -223,6 +231,74 @@ describe('generateAndSign — inapp pathway', () => {
       ),
     ).rejects.toThrow(ValidationError);
   });
+
+  it('uses the EOI source-PDF path (not pdfme HTML) for templateType=eoi', async () => {
+    const fillModule = await import('@/lib/pdf/fill-eoi-form');
+    const pdfModule = await import('@/lib/pdf/generate');
+    const client = await import('@/lib/services/documenso-client');
+    vi.mocked(client.createDocument).mockResolvedValue({
+      id: 'doc-eoi-pdf',
+      status: 'PENDING',
+      recipients: [],
+    });
+    vi.mocked(client.sendDocument).mockResolvedValue({
+      id: 'doc-eoi-pdf',
+      status: 'PENDING',
+      recipients: [],
+    });
+
+    await generateAndSign(
+      setup.inAppTemplateId,
+      setup.portId,
+      { clientId: setup.clientId, interestId: setup.interestId },
+      [{ name: 'C', email: 'c@x.com', role: 'signer', signingOrder: 1 }],
+      'inapp',
+      { ...meta, portId: setup.portId },
+    );
+
+    expect(fillModule.generateEoiPdfFromTemplate).toHaveBeenCalled();
+    expect(pdfModule.generatePdf).not.toHaveBeenCalled();
+  });
+
+  it('falls back to HTML→pdfme for non-EOI template types', async () => {
+    // Create a non-EOI template inline.
+    const [other] = await db
+      .insert(documentTemplates)
+      .values({
+        portId: setup.portId,
+        name: 'Welcome Letter',
+        templateType: 'welcome_letter',
+        bodyHtml: '<p>Welcome {{client.fullName}}</p>',
+        createdBy: 'test',
+      })
+      .returning();
+
+    const fillModule = await import('@/lib/pdf/fill-eoi-form');
+    const pdfModule = await import('@/lib/pdf/generate');
+    const client = await import('@/lib/services/documenso-client');
+    vi.mocked(client.createDocument).mockResolvedValue({
+      id: 'doc-welcome',
+      status: 'PENDING',
+      recipients: [],
+    });
+    vi.mocked(client.sendDocument).mockResolvedValue({
+      id: 'doc-welcome',
+      status: 'PENDING',
+      recipients: [],
+    });
+
+    await generateAndSign(
+      other!.id,
+      setup.portId,
+      { clientId: setup.clientId },
+      [{ name: 'C', email: 'c@x.com', role: 'signer', signingOrder: 1 }],
+      'inapp',
+      { ...meta, portId: setup.portId },
+    );
+
+    expect(pdfModule.generatePdf).toHaveBeenCalled();
+    expect(fillModule.generateEoiPdfFromTemplate).not.toHaveBeenCalled();
+  });
 });
 
 // ─── Pathway: documenso-template ──────────────────────────────────────────────