feat(uat-batch-4): a11y form primitives + click-to-preview + EOI empty-state + lint guards

- FieldError primitive (role=alert, aria-live) — used by Wave 3
  form-error UX work.
- FieldLabel primitive (Label + Info-tooltip slot) — foundational for
  the platform-wide admin-settings tooltip audit.
- ESLint guard against em-dash in user-facing JSX text inside
  src/components + src/app (warning, not error; 111 existing instances
  flagged for follow-up sweep).
- FileGrid card body becomes click-to-preview button (was hidden under
  a kebab); aria-label per row; kebab keeps Download/Rename/Delete.
- DocumentList: title cell on rows with signedFileId opens
  FilePreviewDialog; kebab gains Download action (was missing
  per UAT). Single FilePreviewDialog instance lifted to the parent.
- DocumentList type extended with signedFileId.
- EOI empty state: third ghost button "Mark signed without file"
  wired to existing MarkExternallySignedDialog (parity with
  reservation tab).
- Watcher empty-state padding fix on document-detail.

tsc clean. 1419/1419 vitest. lint clean on touched files.

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

src/components/interests/interest-eoi-tab.tsx

@@ -25,6 +25,7 @@ import { Skeleton } from '@/components/ui/skeleton';
 import { EoiCancelDialog } from '@/components/documents/eoi-cancel-dialog';
 import { EoiGenerateDialog } from '@/components/documents/eoi-generate-dialog';
 import { ExternalEoiUploadDialog } from '@/components/interests/external-eoi-upload-dialog';
+import { MarkExternallySignedDialog } from '@/components/interests/mark-externally-signed-dialog';
 import { SigningProgress } from '@/components/documents/signing-progress';
 import { FilePreviewDialog } from '@/components/files/file-preview-dialog';
 import { apiFetch } from '@/lib/api/client';
@@ -104,6 +105,7 @@ export function InterestEoiTab({ interestId, clientId }: InterestEoiTabProps) {
   const portSlug = useUIStore((s) => s.currentPortSlug);
   const [generateOpen, setGenerateOpen] = useState(false);
   const [uploadSignedOpen, setUploadSignedOpen] = useState(false);
+  const [markSignedOpen, setMarkSignedOpen] = useState(false);
   // Lifted preview state so the View button on every signed-PDF row opens
   // the in-app preview dialog rather than navigating to a presigned URL
   // (which the storage backend serves with Content-Disposition=attachment,
@@ -137,6 +139,7 @@ export function InterestEoiTab({ interestId, clientId }: InterestEoiTabProps) {
         <EmptyEoiState
           onGenerate={() => setGenerateOpen(true)}
           onUploadSigned={() => setUploadSignedOpen(true)}
+          onMarkSigned={() => setMarkSignedOpen(true)}
         />
       )}
 
@@ -197,6 +200,13 @@ export function InterestEoiTab({ interestId, clientId }: InterestEoiTabProps) {
         interestId={interestId}
       />
 
+      <MarkExternallySignedDialog
+        open={markSignedOpen}
+        onOpenChange={setMarkSignedOpen}
+        interestId={interestId}
+        docType="eoi"
+      />
+
       <FilePreviewDialog
         open={!!previewFile}
         onOpenChange={(o) => {
@@ -559,9 +569,11 @@ function SignedPdfPreview({ fileId }: { fileId: string }) {
 function EmptyEoiState({
   onGenerate,
   onUploadSigned,
+  onMarkSigned,
 }: {
   onGenerate: () => void;
   onUploadSigned: () => void;
+  onMarkSigned: () => void;
 }) {
   return (
     <section className="rounded-xl border border-dashed bg-muted/20 p-8 text-center">
@@ -572,7 +584,7 @@ function EmptyEoiState({
         No EOI in flight for this interest
       </h2>
       <p className="mt-1 text-sm text-muted-foreground">
-        Generate the EOI to send it for signing — the signing service handles the signing chain. You
+        Generate the EOI to send it for signing. The signing service handles the signing chain. You
         can also upload a paper-signed copy if it was signed outside the system.
       </p>
       <div className="mt-5 flex flex-wrap items-center justify-center gap-2">
@@ -584,6 +596,10 @@ function EmptyEoiState({
           <Upload className="size-4" aria-hidden />
           Upload paper-signed copy
         </Button>
+        <Button onClick={onMarkSigned} variant="ghost" size="sm" className="gap-1.5">
+          <CheckCircle2 className="size-4" aria-hidden />
+          Mark signed without file
+        </Button>
       </div>
     </section>
   );