Emit Nest build to dist/main.js by compiling only src.

Co-authored-by: Cursor <cursoragent@cursor.com>

tsconfig.build.json

@@ -1,4 +1,5 @@
 {
   "extends": "./tsconfig.json",
+  "include": ["src/**/*"],
   "exclude": ["node_modules", "test", "dist", "**/*spec.ts"]
 }