fix(whatsapp): trim leading whitespace in direct outbound sends (#43539)

Trim leading whitespace from direct WhatsApp text and media caption sends.

Also guard empty text-only web sends after trimming.

src/web/outbound.test.ts

@@ -48,6 +48,34 @@ describe("web outbound", () => {
     expect(sendMessage).toHaveBeenCalledWith("+1555", "hi", undefined, undefined);
   });
 
+  it("trims leading whitespace before sending text and captions", async () => {
+    await sendMessageWhatsApp("+1555", "\n \thello", { verbose: false });
+    expect(sendMessage).toHaveBeenLastCalledWith("+1555", "hello", undefined, undefined);
+
+    const buf = Buffer.from("img");
+    loadWebMediaMock.mockResolvedValueOnce({
+      buffer: buf,
+      contentType: "image/jpeg",
+      kind: "image",
+    });
+    await sendMessageWhatsApp("+1555", "\n \tcaption", {
+      verbose: false,
+      mediaUrl: "/tmp/pic.jpg",
+    });
+    expect(sendMessage).toHaveBeenLastCalledWith("+1555", "caption", buf, "image/jpeg");
+  });
+
+  it("skips whitespace-only text sends without media", async () => {
+    const result = await sendMessageWhatsApp("+1555", "\n \t", { verbose: false });
+
+    expect(result).toEqual({
+      messageId: "",
+      toJid: "1555@s.whatsapp.net",
+    });
+    expect(sendComposingTo).not.toHaveBeenCalled();
+    expect(sendMessage).not.toHaveBeenCalled();
+  });
+
   it("throws a helpful error when no active listener exists", async () => {
     setActiveWebListener(null);
     await expect(

src/web/outbound.ts

@@ -26,7 +26,11 @@ export async function sendMessageWhatsApp(
     accountId?: string;
   },
 ): Promise<{ messageId: string; toJid: string }> {
-  let text = body;
+  let text = body.trimStart();
+  const jid = toWhatsappJid(to);
+  if (!text && !options.mediaUrl) {
+    return { messageId: "", toJid: jid };
+  }
   const correlationId = generateSecureUuid();
   const startedAt = Date.now();
   const { listener: active, accountId: resolvedAccountId } = requireActiveWebListener(
@@ -51,7 +55,6 @@ export async function sendMessageWhatsApp(
     to: redactedTo,
   });
   try {
-    const jid = toWhatsappJid(to);
     const redactedJid = redactIdentifier(jid);
     let mediaBuffer: Buffer | undefined;
     let mediaType: string | undefined;