Update Eclipse IDE landing page and getting started page for 2025-12 R

The getting started page needs to be updated for 2025-09 R

• See https://eclipseide.org/getting-started/
• The release-name.json file also needs to be updated for the New and Noteworthy page to get the updated information.
• Content is under construction at: https://docs.google.com/document/d/1tHYhuD_qQZLESo_lRs7zkem-0AZZ4qgQ1PgZaqA_0qw/edit?tab=t.0#heading=h.3wceper26y4g and should be available / finalized before May 23 2025