feat(logging): replace 207 console.log/error/warn with pino structured logger (#58)

- Add pino + pino-pretty dependencies
- Create src/utils/logger.js with env-based LOG_LEVEL
- Replace all 207 console.log/error/warn calls across 46 source files
- Remove [DEBUG], [ERROR] string prefixes (levels convey this)
- Add pino redact for sensitive fields (mnemonic, privateKey, token, etc.)
- Structured logging with context objects instead of string interpolation
- NODE_ENV=production disables pino-pretty transport

49 files changed, 5601 insertions, 6056 deletions

src/utils/logger.js

@@ -0,0 +1,19 @@
+import pino from 'pino';
+
+const level = process.env.LOG_LEVEL || 'info';
+
+const options = {
+    level,
+    redact: ['*.mnemonic', '*.privateKey', '*.secret', '*.token', '*.password', '*.ENCRYPTION_KEY', '*.BOT_TOKEN'],
+    serializers: {
+        err: pino.stdSerializers.err,
+    },
+};
+
+if (process.env.NODE_ENV !== 'production') {
+    options.transport = { target: 'pino-pretty', options: { colorize: true } };
+}
+
+const logger = pino(options);
+
+export default logger;