Move bot example to examples/bots/ and add .env.example

- Move buy_low_sell_high_bot.py into examples/bots/
- Add .env.example with all config vars documented (no real creds)

Author: gregnazario

examples/bots/.env.example

@@ -0,0 +1,24 @@
+# Decibel Bot Configuration
+# Copy this file to .env and fill in your values:
+#   cp .env.example .env
+
+# Required: Aptos account private key (hex, with 0x prefix)
+PRIVATE_KEY="0x..."
+
+# Required: API key from Geomi (https://geomi.dev)
+APTOS_NODE_API_KEY="aptoslabs_..."
+
+# Network: testnet, mainnet, or netna
+NETWORK="testnet"
+
+# Market to trade (must match a market name on the exchange)
+MARKET="ETH/USD"
+
+# Buy spread: place buy order this % below oracle price
+BUY_SPREAD_PCT="1.0"
+
+# Sell spread: place sell order this % above entry price
+SELL_SPREAD_PCT="1.0"
+
+# Notional order size in USD
+ORDER_SIZE_USD="100"