fix: resolve worker build errors blocking Docker deploy

- Add OPENROUTER_API_KEY (optional) to env schema so tsc can resolve it
- Add pg + @types/pg to worker deps for outbox-listener
- Explicit Error type on pg client error handler

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/config/src/index.ts

@@ -14,6 +14,7 @@ const envSchema = z.object({
   BCRYPT_ROUNDS: z.coerce.number().int().min(4).max(15).default(10),
   JWT_EXPIRES_IN: z.string().default('7d'),
   MEMBER_JWT_EXPIRES_IN: z.string().default('30d'),
+  OPENROUTER_API_KEY: z.string().optional(),
 });
 
 export type Env = z.infer<typeof envSchema>;