fix: change structlog output from JSON to console format

- Switch from JSONRenderer to ConsoleRenderer for human-readable output
- Match logging format used in divine/ and aegis/ repositories
- Maintain structured key-value logging with colored console output
- Use standard timestamp format instead of ISO format

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: codebydivine

src/thegraph_token_api/logger.py

@@ -7,18 +7,18 @@ def get_logger(name: str) -> BoundLogger:
     return structlog.get_logger(name)
 
 
-# Configure structlog for JSON output with consistent formatting
+# Configure structlog for console output consistent with divine/aegis format
 structlog.configure(
     processors=[
         structlog.stdlib.filter_by_level,
         structlog.stdlib.add_logger_name,
         structlog.stdlib.add_log_level,
         structlog.stdlib.PositionalArgumentsFormatter(),
-        structlog.processors.TimeStamper(fmt="iso"),
+        structlog.processors.TimeStamper(fmt="%Y-%m-%d %H:%M:%S"),
         structlog.processors.StackInfoRenderer(),
         structlog.processors.format_exc_info,
         structlog.processors.UnicodeDecoder(),
-        structlog.processors.JSONRenderer(),
+        structlog.dev.ConsoleRenderer(colors=True),
     ],
     context_class=dict,
     logger_factory=structlog.stdlib.LoggerFactory(),