feat(cli): add config module and config command

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

packages/cli/src/index.ts

@@ -1,5 +1,6 @@
 #!/usr/bin/env node
 import { Command } from "commander";
+import { registerConfigCommand } from "./commands/config.js";
 
 const program = new Command();
 
@@ -9,4 +10,6 @@ program
   .version("0.1.0")
   .option("--json", "output as JSON");
 
+registerConfigCommand(program);
+
 program.parse();