feat(cli): add mosaic gateway init command with tier selection wizard

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

packages/cli/package.json

@@ -22,6 +22,7 @@
   },
   "dependencies": {
     "@clack/prompts": "^0.9.0",
+    "@mosaic/config": "workspace:^",
     "@mosaic/mosaic": "workspace:^",
     "@mosaic/prdy": "workspace:^",
     "@mosaic/quality-rails": "workspace:^",

packages/cli/src/cli.ts

@@ -7,6 +7,7 @@ import { registerAgentCommand } from './commands/agent.js';
 import { registerMissionCommand } from './commands/mission.js';
 // prdy is registered via launch.ts
 import { registerLaunchCommands } from './commands/launch.js';
+import { registerGatewayCommand } from './commands/gateway.js';
 
 const _require = createRequire(import.meta.url);
 const CLI_VERSION: string = (_require('../package.json') as { version: string }).version;
@@ -290,6 +291,10 @@ sessionsCmd
     }
   });
 
+// ─── gateway ──────────────────────────────────────────────────────────
+
+registerGatewayCommand(program);
+
 // ─── agent ─────────────────────────────────────────────────────────────
 
 registerAgentCommand(program);

packages/cli/src/commands/gateway.ts

@@ -0,0 +1,78 @@
+import { createInterface } from 'node:readline';
+import { writeFileSync } from 'node:fs';
+import { resolve } from 'node:path';
+import type { Command } from 'commander';
+import {
+  DEFAULT_LOCAL_CONFIG,
+  DEFAULT_TEAM_CONFIG,
+  type MosaicConfig,
+  type StorageTier,
+} from '@mosaic/config';
+
+function ask(rl: ReturnType<typeof createInterface>, question: string): Promise<string> {
+  return new Promise((res) => rl.question(question, res));
+}
+
+async function runInit(opts: { tier?: string; output: string }): Promise<void> {
+  const outputPath = resolve(opts.output);
+  let tier: StorageTier;
+
+  if (opts.tier) {
+    if (opts.tier !== 'local' && opts.tier !== 'team') {
+      console.error(`Invalid tier "${opts.tier}" — expected "local" or "team"`);
+      process.exit(1);
+    }
+    tier = opts.tier;
+  } else {
+    const rl = createInterface({ input: process.stdin, output: process.stdout });
+    const answer = await ask(rl, 'Select tier (local/team) [local]: ');
+    rl.close();
+    const trimmed = answer.trim().toLowerCase();
+    tier = trimmed === 'team' ? 'team' : 'local';
+  }
+
+  let config: MosaicConfig;
+
+  if (tier === 'local') {
+    config = DEFAULT_LOCAL_CONFIG;
+  } else {
+    const rl = createInterface({ input: process.stdin, output: process.stdout });
+    const dbUrl = await ask(
+      rl,
+      'DATABASE_URL [postgresql://mosaic:mosaic@localhost:5432/mosaic]: ',
+    );
+    const valkeyUrl = await ask(rl, 'VALKEY_URL [redis://localhost:6379]: ');
+    rl.close();
+
+    config = {
+      ...DEFAULT_TEAM_CONFIG,
+      storage: {
+        type: 'postgres',
+        url: dbUrl.trim() || 'postgresql://mosaic:mosaic@localhost:5432/mosaic',
+      },
+      queue: {
+        type: 'bullmq',
+        url: valkeyUrl.trim() || 'redis://localhost:6379',
+      },
+    };
+  }
+
+  writeFileSync(outputPath, JSON.stringify(config, null, 2) + '\n');
+  console.log(`\nWrote ${outputPath}`);
+  console.log('\nNext steps:');
+  console.log('  1. Review the generated config');
+  console.log('  2. Run: pnpm --filter @mosaic/gateway exec tsx src/main.ts');
+}
+
+export function registerGatewayCommand(program: Command): void {
+  const gateway = program.command('gateway').description('Gateway management commands');
+
+  gateway
+    .command('init')
+    .description('Generate a mosaic.config.json for the gateway')
+    .option('--tier <tier>', 'Storage tier: local or team (skips interactive prompt)')
+    .option('--output <path>', 'Output file path', './mosaic.config.json')
+    .action(async (opts: { tier?: string; output: string }) => {
+      await runInit(opts);
+    });
+}