fix: resolve runtime crashes in tool-ui components and backend import errors

Backend:
- Remove dead imports (display_image, link_preview, knowledge_base) from tools registry and __init__
- Delete orphaned elif chain (lines 784-1046) in knowledge_base.py left after asyncio.gather refactor
- Add missing NotionAPIError class to notion_history.py

Frontend:
- Add display-image.tsx, link-preview.tsx, scrape-webpage.tsx tool UI components
- Fix GeneratePodcastToolUI: add null guard for no-props render + optional chaining on status/args
- Fix SaveMemoryToolUI/RecallMemoryToolUI: add null guard when rendered without props in provider
- Update launch.json to use pnpm on port 3999

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

surfsense_backend/app/agents/new_chat/tools/registry.py

@@ -54,7 +54,6 @@ from .crypto_realtime import (
     create_get_live_token_data_tool,
     create_get_live_token_price_tool,
 )
-from .display_image import create_display_image_tool
 from .dropbox import (
     create_create_dropbox_file_tool,
     create_delete_dropbox_file_tool,
@@ -85,8 +84,6 @@ from .linear import (
     create_delete_linear_issue_tool,
     create_update_linear_issue_tool,
 )
-from .knowledge_base import create_search_knowledge_base_tool
-from .link_preview import create_link_preview_tool
 from .mcp_tool import load_mcp_tools
 from .notion import (
     create_create_notion_page_tool,