Introduce Search dataclass for query handling (#23)

* Introduce Search dataclass for query handling

Added a Search dataclass to facilitate search queries.

Author: mekarpeles

pyopds2/models.py

@@ -4,6 +4,7 @@
 """
 
 from datetime import datetime
+from dataclasses import dataclass, asdict
 from typing import TYPE_CHECKING, Any, Dict, List, Optional
 
 from pydantic import BaseModel, Field  # field_validator
@@ -242,3 +243,14 @@ def create(
                 catalog.add_pagination(response)
 
         return catalog
+
+@dataclass
+class Search:
+    query: str
+    limit: int
+    offset: Optional[int] = None
+    sort: Optional[str] = None
+
+    def __iter__(self):
+        """Allows **Search(...) to unpack into a dict for DataProvider.search(**s)"""
+        return iter(asdict(self).items())