fix(mosaic): bound promotion transport delivery

packages/mosaic/src/fleet/promotion-transport.spec.ts

@@ -17,10 +17,11 @@ function result(stdout = '', exitCode = 0, stderr = ''): CommandResult {
 }
 
 describe('TmuxPromotionTransport', () => {
-  it('resolves the exact roster seat and sends through the maintained tmux sender', async () => {
+  it('resolves the exact roster seat and sends the registered command literally', async () => {
     const runner = vi
       .fn<CommandRunner>()
       .mockResolvedValueOnce(result('1234 claude 0 0 0 0\n'))
+      .mockResolvedValueOnce(result())
       .mockResolvedValueOnce(result());
     const environmentReader = vi.fn(async () => `MOSAIC_LEASE_SESSION_ID=${sessionId}\0`);
     const transport = new TmuxPromotionTransport({
@@ -39,15 +40,22 @@ describe('TmuxPromotionTransport', () => {
       sessionId,
     });
     expect(environmentReader).toHaveBeenCalledWith(1234);
-    expect(runner).toHaveBeenNthCalledWith(2, '/mosaic/tools/tmux/agent-send.sh', [
+    expect(runner).toHaveBeenNthCalledWith(2, 'tmux', [
       '-L',
       'mosaic-fleet',
-      '-S',
-      expect.stringMatching(/:operator$/),
-      '-s',
-      'claude-seat',
-      '-m',
+      'send-keys',
+      '-t',
+      '=claude-seat:0.0',
+      '-l',
       '/mosaic-promote',
     ]);
+    expect(runner).toHaveBeenNthCalledWith(3, 'tmux', [
+      '-L',
+      'mosaic-fleet',
+      'send-keys',
+      '-t',
+      '=claude-seat:0.0',
+      'Enter',
+    ]);
   });
 });

packages/mosaic/src/fleet/promotion-transport.ts

@@ -1,8 +1,6 @@
 import { readFile } from 'node:fs/promises';
 import {
-  buildAgentSendCommand,
   buildTmuxListPanesCommand,
-  getDefaultOperatorSourceLabel,
   getRosterAgent,
   parseTmuxListPanes,
   resolveFleetPaths,
@@ -10,11 +8,13 @@ import {
   type CommandRunner,
   type FleetRoster,
   RUNTIME_ACCEPTABLE_COMMANDS,
+  socketArgs,
 } from '../commands/fleet.js';
 import { loadFleetRoster } from './fleet-roster-v1.js';
 
 const PROMOTION_COMMAND = '/mosaic-promote';
 const SESSION_ID_PATTERN = /^[a-f0-9]{64}$/;
+const TRANSPORT_COMMAND_TIMEOUT_MS = 5_000;
 
 export interface PromotionTarget {
   bundle: string;
@@ -81,16 +81,34 @@ export class TmuxPromotionTransport implements PromotionTransport {
   }
 
   async sendPromotion(target: PromotionTarget): Promise<void> {
-    const command = buildAgentSendCommand(
-      resolveFleetPaths(this.options.mosaicHome),
-      target.seat,
+    const targetPane = `=${target.seat}:0.0`;
+    const socketName = target.bundle === 'default' ? '' : target.bundle;
+    // Registered Claude commands must arrive as their exact literal text; the
+    // fleet agent sender prepends an identity envelope, so it cannot carry this
+    // command without preventing the UserPromptSubmit matcher from recognizing it.
+    await this.runPromotionCommand([
+      'tmux',
+      ...socketArgs(socketName),
+      'send-keys',
+      '-t',
+      targetPane,
+      '-l',
       PROMOTION_COMMAND,
-      target.bundle === 'default' ? '' : target.bundle,
-      getDefaultOperatorSourceLabel(),
-    );
+    ]);
+    await this.runPromotionCommand([
+      'tmux',
+      ...socketArgs(socketName),
+      'send-keys',
+      '-t',
+      targetPane,
+      'Enter',
+    ]);
+  }
+
+  private async runPromotionCommand(command: string[]): Promise<void> {
     const result = await this.run(command);
     if (result.exitCode !== 0) {
-      throw new Error(`Promotion command delivery failed: ${target.seat}.`);
+      throw new Error('Promotion command delivery failed.');
     }
   }
 
@@ -99,10 +117,28 @@ export class TmuxPromotionTransport implements PromotionTransport {
     if (executable === undefined) {
       throw new Error('Promotion transport command is empty.');
     }
-    return this.options.runner(executable, args);
+    return await withTimeout(this.options.runner(executable, args), TRANSPORT_COMMAND_TIMEOUT_MS);
   }
 }
 
+function withTimeout<T>(operation: Promise<T>, timeoutMs: number): Promise<T> {
+  return new Promise((resolve, reject) => {
+    const timeout = setTimeout(() => {
+      reject(new Error(`Promotion transport command timed out after ${timeoutMs}ms.`));
+    }, timeoutMs);
+    void operation.then(
+      (value) => {
+        clearTimeout(timeout);
+        resolve(value);
+      },
+      (error: unknown) => {
+        clearTimeout(timeout);
+        reject(error);
+      },
+    );
+  });
+}
+
 async function readPaneEnvironment(pid: number): Promise<string> {
   return readFile(`/proc/${pid}/environ`, 'utf8');
 }