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>

server.js

@@ -266,6 +266,7 @@ async function handleApi(req,res,pathname){
     if(cached&&Date.now()-cached.ts<120000)return json(res,200,cached.data,{'Cache-Control':'public, max-age=60'});
     try{
       const r=await Promise.race([chain.memberPublic(id),new Promise((_,rej)=>setTimeout(()=>rej(new Error('Blockchain lookup timed out — try again.')),20000))]);
+      if(r.registered)r.referralUrl=`${getConfig().dappReferralBaseUrl}${encodeURIComponent(id)}`;
       memberCache.set(id,{data:r,ts:Date.now()});
       if(memberCache.size>500)memberCache.delete(memberCache.keys().next().value);
       return json(res,200,r,{'Cache-Control':'public, max-age=60'});