Weighted-random destination redirect — the 'pull a thread' link.

Brand promise: lifelong-learner serendipity, not slot-machine randomness. The category mix (30% tickers / 20% BDCs / 20% lessons / 15% glossary / 15% lore) gives the visitor a different texture each time without ever landing on something the platform doesn't cover.

Sets ol_wander_label cookie (5min, non-HttpOnly) carrying the human-readable destination name. Phase 1F.5 will read this on the destination page and render an italic banner: "you wandered to: COST — Wholesale retail." For now, the cookie is a beachhead.

Adds ?wandered=1 to the redirect URL so destination pages can detect the wander entry point without parsing cookies.