chore: track .env.example, unignore from .gitignore

.env.example

@@ -0,0 +1,56 @@
+# ============================================================
+# CubeAdmin - Environment Variables
+# Copy this file to .env.local and fill in your values
+# ============================================================
+
+# ─── Application ─────────────────────────────────────────────
+PORT=3000
+NODE_ENV=development
+BETTER_AUTH_URL=http://localhost:3000
+
+# Generate with: openssl rand -base64 32
+BETTER_AUTH_SECRET=change-me-with-a-strong-random-secret
+
+# ─── Email (SMTP) ────────────────────────────────────────────
+SMTP_HOST=smtp.example.com
+SMTP_PORT=587
+# Set to true only for port 465 (implicit TLS); false uses STARTTLS
+SMTP_SECURE=false
+SMTP_USER=your-smtp-username
+SMTP_PASS=your-smtp-password
+EMAIL_FROM=CubeAdmin <noreply@yourdomain.com>
+
+# ─── Minecraft Server ────────────────────────────────────────
+# Path to the Minecraft server directory on the host
+MC_SERVER_PATH=/opt/minecraft/server
+
+# RCON (Remote Console) - enable in server.properties
+MC_RCON_HOST=127.0.0.1
+MC_RCON_PORT=25575
+MC_RCON_PASSWORD=change-me-rcon-password
+
+# ─── BlueMap (optional 3D map) ───────────────────────────────
+# URL where BlueMap is accessible (leave empty to disable)
+BLUEMAP_URL=http://localhost:8100
+
+# ─── Database ────────────────────────────────────────────────
+# SQLite database path (relative to project root)
+DATABASE_PATH=./data/cubeadmin.db
+
+# ─── Security ────────────────────────────────────────────────
+# Comma-separated list of trusted origins for CORS/CSRF
+TRUSTED_ORIGINS=http://localhost:3000
+
+# Rate limiting (requests per minute per IP for API routes)
+RATE_LIMIT_RPM=100
+
+# ─── First Admin Account (created on first startup) ──────────
+INITIAL_ADMIN_EMAIL=admin@example.com
+INITIAL_ADMIN_NAME=Administrator
+# This password will be required to change on first login
+INITIAL_ADMIN_PASSWORD=ChangeMe123!
+
+# ─── Docker (used in docker-compose.yml) ─────────────────────
+# Only needed when running via Docker Compose
+MC_DATA_PATH=./mc-data
+BACKUPS_PATH=./backups