fix: OUT messages no longer create unread status + handle Telegram read receipts

Only inbound (IN) messages determine hasUnread in getContacts(). Telegram
read_business_message events are now parsed and processed to auto-mark
contacts as read for the entire team.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

omni_chat/src/worker.ts

@@ -445,9 +445,46 @@ async function upsertContactInbox(input: {
   });
 }
 
+async function handleReadBusinessMessage(env: OmniInboundEnvelopeV1) {
+  const teamId = await resolveTeamId(env);
+  if (!teamId) return;
+
+  const n = env.payloadNormalized ?? ({} as OmniInboundEnvelopeV1["payloadNormalized"]);
+  const externalChatId = String(n.threadExternalId ?? n.contactExternalId ?? "").trim();
+  if (!externalChatId) return;
+
+  const thread = await prisma.omniThread.findFirst({
+    where: { teamId, channel: "TELEGRAM", externalChatId },
+    select: { contactId: true },
+  });
+  if (!thread) return;
+
+  const teamUsers = await prisma.teamMember.findMany({
+    where: { teamId },
+    select: { userId: true },
+  });
+  const now = new Date();
+  // ContactThreadRead is not in omni_chat's Prisma schema, use raw upsert
+  await Promise.all(
+    teamUsers.map((u) =>
+      prisma.$executeRaw`
+        INSERT INTO "ContactThreadRead" ("id", "teamId", "userId", "contactId", "readAt")
+        VALUES (gen_random_uuid(), ${teamId}, ${u.userId}, ${thread.contactId}, ${now})
+        ON CONFLICT ("userId", "contactId") DO UPDATE SET "readAt" = ${now}
+      `,
+    ),
+  );
+  console.log(`[omni_chat] read_business_message: marked contact ${thread.contactId} as read for ${teamUsers.length} users`);
+}
+
 async function ingestInbound(env: OmniInboundEnvelopeV1) {
   if (env.channel !== "TELEGRAM") return;
 
+  if (env.eventType === "read_business_message") {
+    await handleReadBusinessMessage(env);
+    return;
+  }
+
   const teamId = await resolveTeamId(env);
   if (!teamId) {
     console.warn("[omni_chat] skip inbound: team not resolved", env.providerEventId);