feat: add pagination support to search_objects MCP tool

Add page_num parameter to the search_objects tool to enable pagination
control for users. This provides full pagination functionality while
maintaining backward compatibility.

Changes:
- Add page_num parameter with default value of 0 (0-based pagination)
- Update tool description to document pagination parameters
- Enhance docstring to explain page_num and clarify limit as page_size
- Add comprehensive tests for pagination scenarios
- All existing functionality remains unchanged

Users can now paginate through search results:
- search_objects("query") - first page, 20 results
- search_objects("query", limit=50) - first page, 50 results
- search_objects("query", page_num=1) - second page, 20 results
- search_objects("query", limit=10, page_num=5) - sixth page, 10 results

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

Co-Authored-By: Claude <noreply@anthropic.com>

src/cordra_mcp/server.py

@@ -35,14 +35,20 @@ Examples:
 - /author:smith - Find objects by author Smith
 - /name:John AND type:Person - Complex queries
 
+Pagination:
+- Results are paginated with 0-based page numbering
+- Use 'limit' to control page size (default: 20)
+- Use 'page_num' to specify which page to retrieve (default: 0)
+
 Returns a JSON list of matching objects with their full metadata."""
 )
 async def search_objects(
     query: str,
     type: str | None = None,
     limit: int | None = None,
+    page_num: int = 0,
 ) -> str:
-    """Search for digital objects in the Cordra repository.
+    """Search for digital objects in the Cordra repository with pagination support.
 
     Args:
         query: The search query string (Lucene/Solr compatible). Examples:
@@ -50,7 +56,8 @@ async def search_objects(
                - "/author:smith" - Find objects by author Smith
                - "/name:John AND type:Person" - Complex queries
         type: Optional filter by object type (e.g., "Person", "Document", "Project")
-        limit: Optional limit on number of results (default: config max_search_results)
+        limit: Optional page size - number of results per page (default: 20)
+        page_num: Page number to retrieve, 0-based (default: 0 for first page)
 
     Returns:
         JSON string containing list of matching objects with their full metadata
@@ -58,7 +65,7 @@ async def search_objects(
     try:
         # Use provided limit or default page size of 20
         page_size = limit if limit is not None else 20
-        search_result = await cordra_client.find(query, object_type=type, page_size=page_size)
+        search_result = await cordra_client.find(query, object_type=type, page_size=page_size, page_num=page_num)
         results = search_result["results"]
         return json.dumps(results, indent=2)