Mainnet indexer fix + retire testnet copy

- chain.js: derive the chain tip as the MAX height across the RPC pool and scan
  getLogs against that same synced node. Load-balanced public RPCs (publicnode)
  intermittently answer eth_blockNumber from a replica lagging thousands of
  blocks behind, which stalled the mainnet scan (latest < lastBlock, 0 events)
  and could skip freshly-mined events. This unblocks the live ledger + the
  purchase-confirmation email (both driven by the event scan).
- disclaimer: replace the "rehearsal/testnet" section with a live-on-Polygon
  real-money notice (it's live now).
- Point the dead Amoy fallbacks (purchase email tx link, contract-page source
  link) at Polygon mainnet / the verified mainnet contract.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

public/assets/contract.js

@@ -12,8 +12,8 @@
     $('lnkSource').href = src;
     $('lnkSource2').href = src;
   } else {
-    // private rehearsal chain: point at the audited Amoy verification instead
-    const src = 'https://repo.sourcify.dev/contracts/full_match/80002/0xaF47EC401A9B0D570a553b1A1c95D6079083636e/';
+    // fallback if explorer unset: point straight at the Sourcify-verified source
+    const src = 'https://repo.sourcify.dev/contracts/full_match/137/0xBE1ECA72AFF47d13D8E907e523F55eB9e2d365E0/';
     $('lnkExplorer').href = src;
     $('lnkSource').href = src;
     $('lnkSource2').href = src;

public/contract.html

@@ -142,7 +142,7 @@
   </footer>
 </div>
 <script src="/assets/common.js?v=20260908c"></script>
-<script src="/assets/contract.js?v=20260906m"></script>
+<script src="/assets/contract.js?v=20260908p"></script>
 <script src="/assets/chat.js?v=20260906m"></script>
 </body>
 </html>

public/disclaimer.html

@@ -18,8 +18,8 @@
     <p class="muted small">Nothing on the Platform is investment, financial, tax, or legal advice. Do your own research and consult a professional before spending money.</p>
     <h3>Crypto risk</h3>
     <p class="muted small">Purchases settle on a public blockchain using a volatile network token. On-chain transactions are final and irreversible: there are no refunds, chargebacks, or reversals. You are responsible for your wallet, your keys, network fees, and the tax treatment of your activity.</p>
-    <h3>Rehearsal / testnet</h3>
-    <p class="muted small">During any rehearsal or testnet phase, the Platform runs on test tokens with no monetary value. Balances, purchases, and payouts during that phase are for testing only and do not carry over to a live launch.</p>
+    <h3>Live on Polygon</h3>
+    <p class="muted small">The Platform is live on the Polygon mainnet. Purchases and payouts use POL, a real cryptocurrency with real monetary value. Every transaction is real and final — this is not a simulation or test environment.</p>
     <h3>Advertising</h3>
     <p class="muted small">Ads are member-created and auto-approved for speed. InstantAdPay does not endorse and is not responsible for advertised products, sites, or claims. Use your judgment, and report anything broken or inappropriate.</p>
     <h3>Your responsibility</h3>