feat: dockerize full stack (web + api + postgres)

- Multi-stage Dockerfiles for API (NestJS, prisma migrate on start) and web (Vite + nginx reverse proxy)
- docker-compose.yml orchestrating db/api/web with healthcheck and persistent volumes
- nginx proxies /api and /avatars to API; web built with relative API URL
- scripts/docker-up.sh: ExFAT-safe wrapper that strips macOS AppleDouble (._*) sidecars before build
- Conditionally register GoogleStrategy only when GOOGLE_CLIENT_ID is set
- Fix unused-variable TS errors blocking production build

.env.docker.example

@@ -0,0 +1,27 @@
+# Copy to .env.docker and edit before running:
+#   cp .env.docker.example .env.docker
+#   docker compose --env-file .env.docker up -d --build
+
+# ---- Postgres ----
+POSTGRES_USER=tabungin
+POSTGRES_PASSWORD=change-me-strong-password
+POSTGRES_DB=tabungin
+
+# ---- API ----
+# Generate a long random string, e.g.: openssl rand -base64 48
+JWT_SECRET=replace-with-a-long-random-secret
+
+# Public URL where the web UI is served (used for CORS + OAuth callbacks)
+WEB_APP_URL=http://localhost:8080
+
+# Host ports (change if something else is using these)
+WEB_PORT=8080
+API_PORT=3001
+
+# ---- Optional integrations ----
+EXCHANGE_RATE_URL=https://api.exchangerate-api.com/v4/latest/IDR
+GOOGLE_CLIENT_ID=
+GOOGLE_CLIENT_SECRET=
+GOOGLE_CALLBACK_URL=http://localhost:8080/api/auth/google/callback
+OTP_SEND_WEBHOOK_URL=
+OTP_SEND_WEBHOOK_URL_TEST=