AP-449: avoid leaking env variables into build

@yzhoubk reported in Slack that snapshot builds were failing again as in
AP-403. upon further investigation, i discovered that vite was dumping
our entire environment into the build, which could lead to credential
leakage. this scopes to the only environment variable that's needed by
vue's reactivity-related internals.

Author: anarchivist

vite.config.js

@@ -44,6 +44,6 @@ export default defineConfig({
   },
   plugins: [vue(), stripDevCSS()],
   define: {
-    'process.env': process.env
+    'process.env.NODE_ENV': `"${process.env.NODE_ENV}"`
   }
 })