fix(signatures): apply reply signature to replies and forwards

app/(main)/[locale]/page.tsx

@@ -61,6 +61,7 @@ import { Input } from "@/components/ui/input";
 import { FilePreviewModal } from "@/components/files/file-preview-modal";
 import { isFilePreviewable } from "@/lib/file-preview";
 import { appendHtmlSignature, appendPlainTextSignature } from "@/lib/signature-utils";
+import { useSignatureStore } from "@/stores/signature-store";
 import { computeReplyThreadingHeaders } from "@/lib/email-threading";
 import { EML_IMPORT_ACCEPT, expandImportableEmails } from "@/lib/eml-import";
 import { findDraftIdentityId, resolveReplyFrom, type ReplyFromResolution } from "@/lib/reply-identity";
@@ -2615,8 +2616,16 @@ export default function Home() {
 
     // Append signature from the sending identity (fall back to primary
     // when the reply-from lives on the same identity but a different alias).
+    // The signature store's reply signature takes precedence over the legacy
+    // identity signature, matching the composer's send path.
+    const signatureStore = useSignatureStore.getState();
+    const replySigId = signatureStore.getIdentityReplySignatureId(sendingIdentity?.id ?? '');
+    const replySig = replySigId ? signatureStore.getSignatureById(replySigId) : undefined;
+    const signatureSource = replySig
+      ? { htmlSignature: replySig.body, textSignature: replySig.plainText }
+      : sendingIdentity;
     const separator = useSettingsStore.getState().signatureSeparatorEnabled;
-    const finalBody = appendPlainTextSignature(body, sendingIdentity, { separator });
+    const finalBody = appendPlainTextSignature(body, signatureSource, { separator });
 
     // When the identity has an HTML signature, send a matching HTML body so the
     // signature keeps its formatting; appendPlainTextSignature would otherwise
@@ -2627,8 +2636,8 @@ export default function Home() {
       .replace(/</g, '&lt;')
       .replace(/>/g, '&gt;')
       .replace(/\n/g, '<br>');
-    const finalHtmlBody = sendingIdentity?.htmlSignature?.trim()
-      ? appendHtmlSignature(`<div>${escapedBody}</div>`, sendingIdentity, { separator })
+    const finalHtmlBody = signatureSource?.htmlSignature?.trim()
+      ? appendHtmlSignature(`<div>${escapedBody}</div>`, signatureSource, { separator })
       : undefined;
 
     const originalEmailId = selectedEmail.id;