Developers menu drops PUBLIC_ vars — import.meta.env aliasing defeats rsbuild inlining

[mpstaton]

Context:

• Fix-Env-Aliasing-That-Drops-Public-Vars-In-Developers-Menu.md

DevelopersMenu.svelte:32-34 assigns import.meta.env to a local before reading PUBLIC_* off it. rsbuild substitutes the base env object wholesale and no PUBLIC_* keys survive, so PUBLIC_ID_BASE resolves to http://localhost:4000 in production despite being set correctly on the Railway service. ws-url.ts:29 reads the member directly and inlines fine — same repo, same build, opposite outcomes.