feat(cli): websocket client + MCP tool integration

broker-client: full WS client with hello handshake + ack, auto-reconnect
with exponential backoff (1s → 30s capped), in-memory outbound queue
(max 100) during reconnect, 500-entry push buffer for check_messages.

MCP tool integration:
- send_message: "slug:target" prefix or single-mesh fast path
- check_messages: drains push buffers across all clients
- set_status: fans manual override across all connected meshes
- set_summary: stubbed (broker protocol extension needed)
- list_peers: stubbed — lists connected mesh slugs + statuses

manager module holds Map<meshId, BrokerClient>, starts on MCP server
boot for every joined mesh in ~/.claudemesh/config.json.

new CLI command: seed-test-mesh injects a mesh row for dev testing.

also fixes a broker-side hello race: handleHello sent hello_ack before
the caller closure assigned presenceId, so clients sending right after
the ack hit the no_hello check. Fix: return presenceId, caller sets
closure var, THEN sends hello_ack. Queue drain is fire-and-forget now.

round-trip verified: two clients, A→B, push received with correct
senderPubkey + ciphertext. 44/44 broker tests still pass.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/broker/src/index.ts

@@ -267,7 +267,7 @@ function sendError(
 async function handleHello(
   ws: WebSocket,
   hello: Extract<WSClientMessage, { type: "hello" }>,
-): Promise<string | null> {
+): Promise<{ presenceId: string; memberDisplayName: string } | null> {
   // Capacity check BEFORE touching DB.
   const existing = connectionsPerMesh.get(hello.meshId) ?? 0;
   if (existing >= env.MAX_CONNECTIONS_PER_MESH) {
@@ -308,8 +308,12 @@ async function handleHello(
     presence_id: presenceId,
     session_id: hello.sessionId,
   });
-  await maybePushQueuedMessages(presenceId);
-  return presenceId;
+  // Drain any queued messages in the background. The hello_ack is
+  // sent by the CALLER after it assigns presenceId — sending it here
+  // races the caller's closure assignment, causing subsequent client
+  // messages to fail the "no_hello" check.
+  void maybePushQueuedMessages(presenceId);
+  return { presenceId, memberDisplayName: member.displayName };
 }
 
 async function handleSend(
@@ -348,7 +352,22 @@ function handleConnection(ws: WebSocket): void {
     try {
       const msg = JSON.parse(raw.toString()) as WSClientMessage;
       if (msg.type === "hello") {
-        presenceId = await handleHello(ws, msg);
+        const result = await handleHello(ws, msg);
+        if (!result) return;
+        presenceId = result.presenceId;
+        // Ack AFTER closure assignment — subsequent client messages
+        // arriving immediately after will now see a non-null presenceId.
+        try {
+          ws.send(
+            JSON.stringify({
+              type: "hello_ack",
+              presenceId: result.presenceId,
+              memberDisplayName: result.memberDisplayName,
+            }),
+          );
+        } catch {
+          /* ws closed during hello */
+        }
         return;
       }
       if (!presenceId) {

apps/broker/src/types.ts

@@ -95,6 +95,13 @@ export interface WSAckMessage {
   queued: boolean;
 }
 
+/** Broker → client: hello handshake acknowledgement. */
+export interface WSHelloAckMessage {
+  type: "hello_ack";
+  presenceId: string;
+  memberDisplayName: string;
+}
+
 /** Broker → client: structured error. */
 export interface WSErrorMessage {
   type: "error";
@@ -108,4 +115,8 @@ export type WSClientMessage =
   | WSSendMessage
   | WSSetStatusMessage;
 
-export type WSServerMessage = WSPushMessage | WSAckMessage | WSErrorMessage;
+export type WSServerMessage =
+  | WSHelloAckMessage
+  | WSPushMessage
+  | WSAckMessage
+  | WSErrorMessage;