wip-banner-system: full banner pool, stack all 300x250s, footer 728x90

Banner spec from Ryan:

- 728x90 header (every page): pool is now LiveU only; rotates when more
  728x90 entries are added to ads.ts.
- 728x90 below main menu on article pages: removed (was the article-top
  AdSlot stub).
- 728x90 footer (every page): replaces the old 300x250 rocket.new
  placeholder in Footer.tsx. Rotates from the same ADS_728X90 pool.
- 300x250 sidebar: now renders EVERY entry in ADS_300X250 stacked
  vertically, shuffled per page-view. Pool: AJA, Zixi, Telycam, LiveU,
  Lectrosonics, Opengear, Studio Hero, Magewell. Adding more entries to
  ads.ts auto-grows the stack.
- 300x600 fixed slot: Blackmagic (Adsanity ad-210571), top of sidebar,
  never rotated.

Implementation:

- ads.ts: Ad interface now allows either src (local image) or adsanity_id
  (iframe). New rotateAll() returns ALL ads of a size shuffled; pickAds
  kept for ArticleBody bounded slots.
- AdImage.tsx: dropped the legacy ADSANITY_CAMPAIGN_MAP label fallback —
  ads.ts is now the single source of truth, so Telycam (no adsanity_id)
  renders its local GIF instead of the iframe.
- SidebarAdStack.tsx: rotateAll(300x250) instead of pickAds with a
  count cap. count prop removed; callers updated.
- NewsArticleDetailClient.tsx: removed article-top 728x90 stub.
- Footer.tsx: 728x90 AdImage in place of the 300x250 placeholder.
- LeaderboardAd.tsx: deleted (was unused after the earlier home-page
  cleanup).
- PENDING_ads.md: rewritten — Adsanity IDs to verify (Studio Hero,
  Blackmagic) and optional local-file upgrades.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/news/[slug]/NewsArticleDetailClient.tsx

@@ -283,11 +283,6 @@ export default function NewsArticleDetailClient({
         </div>
       </div>
 
-      {/* Top leaderboard */}
-      <div className="max-w-container mx-auto px-4 pt-6">
-        <AdSlot zone="article-top" size="728x90" />
-      </div>
-
       {/* Article */}
       <article className="max-w-container mx-auto px-4 py-8 md:py-12">
         <div className="grid grid-cols-1 lg:grid-cols-12 gap-8">
@@ -453,8 +448,8 @@ export default function NewsArticleDetailClient({
 
           {/* Sidebar */}
           <aside className="lg:col-span-4 space-y-6">
-            {/* Blackmagic 300x600 fixed at top + rotating 300x250 banners */}
-            <SidebarAdStack count={4} />
+            {/* Blackmagic 300x600 fixed at top + every 300x250 banner stacked */}
+            <SidebarAdStack />
 
             {/* Related Articles Sidebar */}
             <div className="bg-[#111] border border-[#222] p-5">