NAS syndication adapter (feature-flagged off): push banner/text to Network Ad Space, reconcile delivery into unified credit pool

- nas.js: direct-MySQL writer mirroring CTB's proven payments+sponsorads path (approved:1, pid 1/2, catid 5, remaining counts DOWN)
- Create-time push for banner/text; pause/resume mirrors to NAS deactivate/topUp
- reconcileNas() 5-min loop: reads served, charges delta credits to the shared budget, stops NAS ad when budget dry
- Campaign row shows IAP + '+N net' network views (differentiated stats)
- Inert unless NAS_DB_* env is set; zero prod impact until enabled
- Also: rename Inbox sub-tab to 'Inbox Ads'

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

public/view.html

@@ -4,7 +4,7 @@
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width,initial-scale=1">
 <title>Viewing ad — InstantAdPay</title>
-<link rel="stylesheet" href="/assets/site.css?v=20260905x">
+<link rel="stylesheet" href="/assets/site.css?v=20260905y">
 <style>
   html,body{height:100%;margin:0;overflow:hidden}
   .vw{display:flex;flex-direction:column;height:100vh;height:100dvh;background:var(--bg,#04110c);color:var(--ink,#e8fff7)}
@@ -43,6 +43,6 @@
   </div>
   <iframe class="vframe" id="vFrame" sandbox="allow-scripts allow-same-origin allow-forms allow-popups" referrerpolicy="no-referrer" title="Advertiser site"></iframe>
 </div>
-<script src="/assets/view.js?v=20260905x"></script>
+<script src="/assets/view.js?v=20260905y"></script>
 </body>
 </html>