Regenerate search-documents from spec commit eb3c71aa

Changes:
- Accept: Remove KnowledgeSourceIngestionPermissionOption enum and property
- Accept: Add KnowledgeBaseModelWebSummarizationActivityRecord type
- Accept: Updated accept header logic in operations
- Reject: Keep elapsedInMs property name (not elapsedMs)
- Reject: Keep serializers returning item (not empty {})
- Remove empty DebugInfo interface

Additional fixes:
- Fix type compatibility in serviceUtils.ts conversion functions
- Update KnowledgeRetrievalClient for new generated client signature
- Fix SearchClient helper methods return types
- Fix pagingHelpers.ts and walk.ts pre-existing type errors

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: srbalakr