Member dashboard: drill-down tree, list view, legend, and strategy-aware referral tool

- "Your team" now covers the member's FULL leg with click-to-drill
  pyramid, breadcrumb, and a list-view toggle (mirrors the admin matrix).
- Legend under both the member tree and admin matrix explaining the
  qualified checkmark, tier badges, and downline rollup.
- "Share this position" card: while under 2/2 it's a personal recruiting
  tool — per-member QR (vendored qrcode-generator, CSP-safe), copy link,
  and a join CTA carrying the member's ID as sponsor. At 2/2 the page
  automatically retires the link and redirects sharing to the team
  rotator, so personal referrals can't undermine the moving-link
  strategy.

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

chain.js

@@ -437,7 +437,7 @@ async function memberPublic(id) {
     const inc = await fetchIncome(id);
     out.income = inc.map(p => ({ fromId: p.fromId, pol: p.pol, ts: p.ts, desc: describeIncome(p.fromTier, p.level, p.pol) })).reverse().slice(0, 50);
   } catch (e) { out.income = []; }
-  out.subtree = getSubtree(id, 3);
+  out.subtree = getSubtree(id, 99); // full leg — the dashboard drills down client-side
   const chain = [];
   const seen = new Set([id]);
   let cur = m.uplineId;