chore: add .env.example config template with all options

- Full config template with comments for every setting
- start.sh auto-loads .env if present
- Covers: LLM, DB, Auth, IoT, Voice, Platform Bridge, Search, CORS, WS

.env.example

@@ -0,0 +1,84 @@
+# ============================================
+# Cyrene v2 配置文件 (.env)
+# 复制为 .env 后修改
+# ============================================
+
+# ---- 运行环境 ----
+ENV=development
+LOG_LEVEL=debug
+
+# ---- 服务器 ----
+PORT=8080
+HOST=0.0.0.0
+
+# ---- 数据库 (PostgreSQL + pgvector) ----
+POSTGRES_HOST=localhost
+POSTGRES_PORT=5432
+POSTGRES_USER=cyrene
+POSTGRES_PASSWORD=cyrene_pass
+POSTGRES_DB=cyrene_ai
+
+# ---- LLM API ----
+LLM_API_URL=https://api.openai.com/v1
+LLM_API_KEY=sk-xxxxx
+LLM_MODEL=gpt-4o
+LLM_FALLBACK_MODEL=gpt-4o-mini
+
+# ---- 记忆嵌入 (可选) ----
+# 不配置时使用本地 n-gram 文本相似度
+# EMBEDDING_API_URL=http://localhost:11434/v1
+# EMBEDDING_MODEL=bge-m3
+
+# ---- 认证 ----
+JWT_SECRET=change-me-to-a-random-string-at-least-32-characters-long
+ADMIN_USERNAME=admin
+ADMIN_PASSWORD=admin12345
+REGISTRATION_ENABLED=true
+
+# ---- IoT 设备提供者 ----
+# mock      = 8 个模拟智能家居设备 (开发测试用)
+# none      = 禁用 IoT
+# 未来: homeassistant / mqtt
+IOT_PROVIDER=mock
+
+# ---- 语音服务 ----
+# DASHSCOPE_API_KEY=sk-xxxxx
+TTS_PROVIDER=edge-tts
+ASR_PROVIDER=dashscope
+
+# ---- 后台思考 ----
+ENABLE_BACKGROUND_THINKING=true
+THINK_INTERVAL_SEC=300
+THINK_SILENCE_TIMEOUT_SEC=120
+
+# ---- 平台桥接 ----
+# QQ (OBv11 协议)
+# QQ_OBV11_WS_URL=ws://localhost:3001
+# QQ_ACCESS_TOKEN=
+# QQ_BOT_QQ=
+
+# Telegram
+# TG_BOT_TOKEN=
+
+# Discord
+# DC_BOT_TOKEN=
+
+# Webhook
+# WEBHOOK_LISTEN_ADDR=:9000
+
+# ---- 搜索 (SearXNG) ----
+# SEARXNG_URL=http://localhost:8088
+
+# ---- 数据目录 ----
+DATA_DIR=./data
+PERSONA_DIR=./internal/persona
+
+# ---- 跨域 ----
+ALLOWED_ORIGINS=http://localhost:5173,http://localhost:3000
+
+# ---- WebSocket ----
+WS_MAX_CONNECTIONS=1000
+SESSION_IDLE_TIMEOUT_MIN=30
+
+# ---- 时区 ----
+TZ=Asia/Shanghai