feat: initial polymarket copy trade tool

- Watcher: polls Data API for trader activity
- Executor: buy/sell with market orders + retry logic
- Position manager: JSON-based state tracking
- Auto-sell: limit orders at profit target
- Redeemer: check & redeem winning positions on-chain
- Config: env-based settings with validation
- DRY_RUN mode for safe testing

src/utils/logger.js

@@ -0,0 +1,34 @@
+const COLORS = {
+    reset: '\x1b[0m',
+    bright: '\x1b[1m',
+    dim: '\x1b[2m',
+    red: '\x1b[31m',
+    green: '\x1b[32m',
+    yellow: '\x1b[33m',
+    blue: '\x1b[34m',
+    magenta: '\x1b[35m',
+    cyan: '\x1b[36m',
+    white: '\x1b[37m',
+};
+
+function timestamp() {
+    return new Date().toISOString().replace('T', ' ').substring(0, 19);
+}
+
+function formatMsg(level, color, emoji, ...args) {
+    const ts = timestamp();
+    const prefix = `${COLORS.dim}[${ts}]${COLORS.reset} ${color}${emoji} ${level}${COLORS.reset}`;
+    console.log(prefix, ...args);
+}
+
+const logger = {
+    info: (...args) => formatMsg('INFO', COLORS.blue, 'ℹ️ ', ...args),
+    success: (...args) => formatMsg('SUCCESS', COLORS.green, '✅', ...args),
+    warn: (...args) => formatMsg('WARN', COLORS.yellow, '⚠️ ', ...args),
+    error: (...args) => formatMsg('ERROR', COLORS.red, '❌', ...args),
+    trade: (...args) => formatMsg('TRADE', COLORS.magenta, '📊', ...args),
+    watch: (...args) => formatMsg('WATCH', COLORS.cyan, '👀', ...args),
+    money: (...args) => formatMsg('MONEY', COLORS.green, '💰', ...args),
+};
+
+export default logger;

src/utils/state.js

@@ -0,0 +1,48 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const DATA_DIR = path.join(__dirname, '..', '..', 'data');
+
+// Ensure data directory exists
+if (!fs.existsSync(DATA_DIR)) {
+    fs.mkdirSync(DATA_DIR, { recursive: true });
+}
+
+/**
+ * Read JSON state file
+ * @param {string} filename - File name (e.g., "positions.json")
+ * @param {*} defaultValue - Default value if file doesn't exist
+ * @returns {*} Parsed JSON data
+ */
+export function readState(filename, defaultValue = {}) {
+    const filePath = path.join(DATA_DIR, filename);
+    try {
+        if (fs.existsSync(filePath)) {
+            const data = fs.readFileSync(filePath, 'utf-8');
+            return JSON.parse(data);
+        }
+    } catch (err) {
+        console.error(`Error reading state file ${filename}:`, err.message);
+    }
+    return defaultValue;
+}
+
+/**
+ * Write JSON state file (atomic write via temp file)
+ * @param {string} filename - File name (e.g., "positions.json")
+ * @param {*} data - Data to write
+ */
+export function writeState(filename, data) {
+    const filePath = path.join(DATA_DIR, filename);
+    const tempPath = filePath + '.tmp';
+    try {
+        fs.writeFileSync(tempPath, JSON.stringify(data, null, 2), 'utf-8');
+        fs.renameSync(tempPath, filePath);
+    } catch (err) {
+        console.error(`Error writing state file ${filename}:`, err.message);
+        // Clean up temp file if rename failed
+        try { fs.unlinkSync(tempPath); } catch (_) { }
+    }
+}