feat(fleet): comms-block emitter + FLEET-LAUNCH runbook (#633) (#638)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

packages/mosaic/src/commands/fleet.ts

@@ -7,6 +7,7 @@ import { spawn } from 'node:child_process';
 import * as readline from 'node:readline';
 import type { Command } from 'commander';
 import YAML from 'yaml';
+import { resolveCommsBlock } from '../fleet/comms-onboarding.js';
 
 /**
  * A function that spawns a command with inherited stdio (TTY passthrough).
@@ -1359,6 +1360,23 @@ export function registerFleetAgentCommands(
       }
     });
 
+  agentCommand
+    .command('comms-block <role>')
+    .description(
+      "Print the Fleet Comms cheat-sheet for a roster role (preview a peer's peer-reach view)",
+    )
+    .option('--host <host>', 'Override the fleet host (preview a cross-host peer view)')
+    .action((role: string, opts: { host?: string }) => {
+      const mosaicHome = resolveMosaicHomeFromCommand(agentCommand, deps.mosaicHome);
+      const res = resolveCommsBlock(mosaicHome, role, opts.host);
+      if (!res.ok) {
+        console.error(`[mosaic] comms-block: ${res.error}`);
+        process.exitCode = 1;
+        return;
+      }
+      console.log(res.output);
+    });
+
   agentCommand
     .command('status [agent]')
     .description('Show tmux status for the local fleet or one agent')