Add home "team by the numbers" showcase + why-a-winning-team-pays

Public /api/public/org-stats (from config.orgRootId, default 21) feeds a
prominent home-page band: share of the whole network, team size,
generations deep, and on-chain POL to the team — populated by bridge.js,
section hides itself if stats aren't ready. Paired with three mechanics
cards (spillover fills your matrix, depth pays as it climbs, the rotation
qualifies you) that make the "winning team" case honestly, plus the risk
caveat ("most participants may not profit") and a disclaimer link.
Live: 51.1% of members, 48 in the org, 10 generations, 25,423 POL.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

chain.js

@@ -527,8 +527,10 @@ function getOrgShare(rootId) {
   const orgBelow = root.downCount || 0;
   const orgMembers = orgBelow + 1;
   const orgPol = (rm.earnedPol || 0) + (root.downPol || 0);
+  let generations = 0;
+  (function depth(n, dep) { if (!n) return; if (dep > generations) generations = dep; depth(n.left, dep + 1); depth(n.right, dep + 1); })(root, 0);
   return {
-    ...base, found: true, orgBelow, orgMembers,
+    ...base, found: true, orgBelow, orgMembers, generations,
     memberPct: +(100 * orgMembers / totalMembers).toFixed(1),
     belowPct: +(100 * orgBelow / totalMembers).toFixed(1),
     orgPol: +orgPol.toFixed(2),