implement client-side pending_date filtering for PENDING properties

- Fix PENDING properties to filter by pending_date instead of list_date
- Add client-side filtering for PENDING as server-side pending_date filter is broken
- Include contingent properties without pending_date for comprehensive results
- Enhance documentation to clarify past_days behavior per listing type
- Add property_history field to GraphQL queries for future enhancements
- Add comprehensive test for pending date filtering functionality
- Optimize filtering logic with helper methods for better maintainability

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

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

pyproject.toml

@@ -1,9 +1,9 @@
 [tool.poetry]
 name = "homeharvest"
-version = "0.5.2"
+version = "0.6.0"
 description = "Real estate scraping library"
 authors = ["Zachary Hampton <zachary@bunsly.com>", "Cullen Watson <cullen@bunsly.com>"]
-homepage = "https://github.com/Bunsly/HomeHarvest"
+homepage = "https://github.com/ZacharyHampton/HomeHarvest"
 readme = "README.md"
 
 [tool.poetry.scripts]