#959 Remove design notes from new-selection docs

[digitaldiina]

• api/search/find-selection/convert-to-new-date-range-operators.md

  • Remove requirement section
  • Move the remaining content to date-range-as-criteria.md (anchor #convert)
  • Redirect

• api/search/find-selection/date-range-as-criteria.md

  • Update metadata
  • Bump years by 6 (current 2025) so it doesn't read as outdated/unmaintained
  • Link to the new appended section's anchor instead of file

• api/search/find-selection/typical-search.md

  • Update metadata
  • Cut pure design note sections
  • Rephrase "will be used" and similar futuristic constructs
  • Rewrite introductory paragraphs/sections
  • Reduce repetition in data model
  • Improve formatting
  • Delete screenshot no longer in use

[SuperOfficeDevNet]

Looks good