feat: initialize nuntius project with full server implementation

.env.example

@@ -0,0 +1,23 @@
+# nuntius — environment variables for runtime secrets.
+#
+# Copy this file to /etc/nuntius/.env on the server and fill in real values.
+# Permissions: chmod 600 (readable only by root / the nuntius user).
+#
+# The systemd service (deploy/nuntius.service) loads this file via
+# EnvironmentFile= and exports every variable to nuntius at startup.
+# The JSON config substitutes ${VAR_NAME} references from this file
+# before parsing, so secrets can stay out of config.json.
+
+# Required: SMTP password used by every form. Reference in config.json as
+# ${NUNTIUS_SMTP_PASSWORD}.
+NUNTIUS_SMTP_PASSWORD=change-me-to-your-smtp-password
+
+# Optional: override the listen port. Config.json `server.port` takes
+# precedence; this is only useful if you want to flip the port without
+# editing JSON.
+# NUNTIUS_PORT=8080
+
+# Optional: override the data directory for newsletter subscribers.
+# Config.json `data_dir` takes precedence; this is only useful if you
+# want to point storage elsewhere (e.g. a dedicated volume).
+# NUNTIUS_DATA_DIR=/var/lib/nuntius/data