style: align stats/base/dists/uniform/ctor with namespace conventions

Added missing `npm` engine constraint (`>2.7.0`) to package.json `engines` (present in 93% of sibling packages in `stats/base/dists/uniform`).

Author: claude

lib/node_modules/@stdlib/stats/base/dists/uniform/ctor/package.json

@@ -34,7 +34,8 @@
   "dependencies": {},
   "devDependencies": {},
   "engines": {
-    "node": ">=0.10.0"
+    "node": ">=0.10.0",
+    "npm": ">2.7.0"
   },
   "os": [
     "aix",