fix: #3610651 Privacy footer link, homepage and Stories card links, and distinct demo media

Related issue: #3610651 Package the Educare site template recipe

Three demo-content and link fixes found in the regression sweep:

• Footer "Privacy policy" link resolves for anonymous. Basic Privacy ships its policy node unpublished, so its footer link is access-hidden for anonymous and its /privacy-policy URL 404s. Educare already publishes its own /privacy page; this adds an Educare footer menu link to /privacy so anonymous visitors get a working link.
• Homepage and Stories pattern card links repointed to real routes. /about-varbase (a 404) now points to /about; the Stories teaser cards that all funnelled to one page now point to /news (news teasers) and /events (the open-day card). Every fixed link resolves 200.
• Distinct demo media. Two pairs of image files shared one filename/URI and collided on install (the second auto-suffixed), so each pair rendered the same photo. Each file now has a distinct filename/URI, and the two mislabeled items get accurate names and alt text (a campus-event speaker photo and a library-computer photo).

Verified on a fresh drush site:install recipes/educare: anonymous footer Privacy policy -> /privacy (200), all fixed card links 200, four distinct media render with no auto-suffix collision.

AI-Generated: Yes

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