fix: #3607228 Enable the Quicklinks footer menu and fix the logo variant

The footer diverged from the design in three ways, all real bugs rather than styling gaps, found by diffing against the golden reference site (main-bvxea6i-q45y2z2rcgmea.eu.platformsh.site).

Quicklinks menu never rendered. The Quicklinks menu link already existed in the secondary menu, but shipped enabled: false, and the four children (Learn / Explore / Impact / Act) each shipped parent: '' instead of pointing at it — so they rendered as four flat, unlabelled links instead of a Quicklinks-headed group. Fixed both: Quicklinks is now enabled, and all four children set parent: 'menu_link_content:d6d4c475-2a54-4c8c-bf68-ae0e40ccb63d'.

Wrong logo variant in the footer. canvas.page_region.vartheme_bs5_horizonaid.footer pointed the card-logo component at full-logo-light.svg. On the footer's navy background that variant's wordmark is dark-on-dark and invisible — only the icon glyph showed. Repointed to full-logo-dark.svg, which golden uses in the same spot.

The four Quicklinks pointed at nothing. All four shipped uri: 'internal:#'. Pointed each at a real destination:

• Learn → /resources
• Explore → /programs
• Act → /donate
• Impact → a new /impact page (none existed). Home's own "Explore Our Impact" button already links to /countries, so there was a precedent for treating impact as real, already-published data rather than new copy — the new page reuses exactly that: the same three global figures the homepage shows (20K+ Lives Protected, 137K+ Legal Aid Hours, 11K+ Communities Served), plus the five per-programme figures already authored on each programme page, plus the homepage's own transparency paragraph. Nothing on it is invented.

Not touched, and not a regression: the social icons linking to Vardot's own accounts — also present in golden as-is, worth a separate decision, not something this fix should silently change.

Verified on a clean install: footer matches golden's screenshot exactly, and all four Quicklinks resolve to real, working pages.

AI-Generated: Yes

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