feat: turbostarter boilerplate

Production-ready Next.js boilerplate with:
- Runtime env validation (fail-fast on missing vars)
- Feature-gated config (S3, Stripe, email, OAuth)
- Docker + Coolify deployment pipeline
- PostgreSQL + pgvector, MinIO S3, Better Auth
- TypeScript strict mode (no ignoreBuildErrors)
- i18n (en/es), AI modules, billing, monitoring

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/mobile/env.config.ts

@@ -0,0 +1,55 @@
+import { defineEnv } from "envin";
+import * as z from "zod";
+
+import { preset as analytics } from "@turbostarter/analytics-mobile/env";
+import { preset as monitoring } from "@turbostarter/monitoring-mobile/env";
+import { envConfig } from "@turbostarter/shared/constants";
+import { ThemeColor, ThemeMode } from "@turbostarter/ui";
+
+const castStringToBool = z.preprocess((val) => {
+  if (typeof val === "string") {
+    if (["1", "true"].includes(val.toLowerCase())) return true;
+    if (["0", "false"].includes(val.toLowerCase())) return false;
+  }
+  return val;
+}, z.coerce.boolean());
+
+export default defineEnv({
+  ...envConfig,
+  extends: [analytics, monitoring],
+  clientPrefix: "EXPO_PUBLIC_",
+  client: {
+    EXPO_PUBLIC_AUTH_PASSWORD: castStringToBool.optional().default(true),
+    EXPO_PUBLIC_AUTH_MAGIC_LINK: castStringToBool.optional().default(false),
+    EXPO_PUBLIC_AUTH_ANONYMOUS: castStringToBool.optional().default(true),
+    EXPO_PUBLIC_GOOGLE_CLIENT_ID: z.string().optional().default(""),
+
+    EXPO_PUBLIC_SITE_URL: z.url(),
+    EXPO_PUBLIC_DEFAULT_LOCALE: z.string().optional().default("en"),
+    EXPO_PUBLIC_THEME_MODE: z
+      .enum(ThemeMode)
+      .optional()
+      .default(ThemeMode.SYSTEM),
+    EXPO_PUBLIC_THEME_COLOR: z
+      .enum(ThemeColor)
+      .optional()
+      .default(ThemeColor.ORANGE),
+  },
+  env: {
+    ...process.env,
+    EXPO_PUBLIC_SITE_URL: process.env.EXPO_PUBLIC_SITE_URL,
+    EXPO_PUBLIC_DEFAULT_LOCALE: process.env.EXPO_PUBLIC_DEFAULT_LOCALE,
+    EXPO_PUBLIC_THEME_MODE: process.env.EXPO_PUBLIC_THEME_MODE,
+    EXPO_PUBLIC_THEME_COLOR: process.env.EXPO_PUBLIC_THEME_COLOR,
+
+    EXPO_PUBLIC_AUTH_PASSWORD: process.env.EXPO_PUBLIC_AUTH_PASSWORD,
+    EXPO_PUBLIC_AUTH_MAGIC_LINK: process.env.EXPO_PUBLIC_AUTH_MAGIC_LINK,
+    EXPO_PUBLIC_AUTH_ANONYMOUS: process.env.EXPO_PUBLIC_AUTH_ANONYMOUS,
+    EXPO_PUBLIC_GOOGLE_CLIENT_ID: process.env.EXPO_PUBLIC_GOOGLE_CLIENT_ID,
+
+    EXPO_PUBLIC_POSTHOG_KEY: process.env.EXPO_PUBLIC_POSTHOG_KEY,
+    EXPO_PUBLIC_POSTHOG_HOST: process.env.EXPO_PUBLIC_POSTHOG_HOST,
+    EXPO_PUBLIC_SENTRY_DSN: process.env.EXPO_PUBLIC_SENTRY_DSN,
+    EXPO_PUBLIC_SENTRY_ENVIRONMENT: process.env.EXPO_PUBLIC_SENTRY_ENVIRONMENT,
+  },
+});