fix(api): pass merged env to c.env in dev server

[devtanluc]

Problem

Under bun dev, the Google sign-in button never renders even with GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET set in .env.local. config.socialProviders returns [].

Cause

apps/api/dev.ts merges process.env over the Wrangler bindings, but passes the result only to createAuth(db, env). tRPC builds ctx.env from c.env, which is {} in the Bun dev server because no bindings are passed to app.fetch(). Better Auth and tRPC therefore see different environments. Production is unaffected, since the Workers runtime fills c.env.

Any procedure that reads ctx.env was broken in dev, for example the ones that depend on Stripe variables.

Fix

Assign the merged env to c.env before next():

c.set("auth", createAuth(db, env));
c.env = env; // tRPC copies c.env into ctx.env; keep it in sync with auth
await next();

The assignment is per request, so shared bindings are not mutated.

Verification

• Ran apps/api/dev.ts with Google credentials set: config.socialProviders returns [] before the change and ["google"] after
• bun run test --run, bun typecheck, bun lint and bun run format:check pass
• Not tested on Windows (the reporter's platform)
• No regression test: it would need heavy mocking of Wrangler and the database for a one-line change

[koistya]

Merged. Thanks @devtanluc, and welcome! Nice first PR – the debug output in the description made this a 10-second review. Google button now shows up in dev. Come break something else 😄