refactor(api): update import statements to use relative paths

- Changed import statements in `agents.py` and `threads.py` to utilize relative paths for improved module organization and clarity.

sdk/kortix/api/agents.py

@@ -3,7 +3,7 @@ from typing import Optional, List, Dict, Any
 from dataclasses import dataclass, asdict
 import json
 
-from tools import AgentPressTools
+from ..tools import AgentPressTools
 
 
 @dataclass

sdk/kortix/api/threads.py

@@ -4,7 +4,7 @@ import httpx
 from datetime import datetime
 
 # Import from shared models
-from models import (
+from ..models import (
     Role,
     MessageType,
     BaseMessage,