av: clone broadcastbeat sources + AV Beat rebrand (Phase 1)

- Replaces the prior Rocket scaffold (saved on pre-bb-clone-rollback branch)
- Domain: broadcastbeat.com -> avbeat.com
- Brand: Broadcast Beat -> AV Beat
- Slug: broadcastbeat -> avbeat (package, identifiers)
- Schema fallback: bb -> av (env var name unchanged)
- Placeholder AV BEAT logo (gold->red gradient) at /assets/logos/av.svg
- All BB/RMP logo references repointed

Outstanding before public DNS swap:
  - Supabase av schema bootstrap (mirror of bb tables)
  - WordPress archive import (avbeat-com -> av.articles)
  - Coolify env vars
  - dev-avbeat.onsethost.com staging deploy + visual review

PENDING_ads.md

@@ -1,4 +1,4 @@
-# Pending — broadcastbeat.com tonight's deferred work
+# Pending — avbeat.com tonight's deferred work
 
 ## Featured-image backfill (P0-1, deferred)
 
@@ -12,7 +12,7 @@ in Supabase storage) is **NOT done**. The smoke-test attempt
 `/tmp/bb-image-backfill.py` ran on coolify01:
 
 - Matrox+Amagi smoke article (`matrox-video-and-amagi-collaborate-...`):
-  Wayback returned no archived snapshot of `https://www.broadcastbeat.com/<slug>/`,
+  Wayback returned no archived snapshot of `https://www.avbeat.com/<slug>/`,
   so the og:image extraction path didn't apply. Many of the broken-image
   articles are recent NAB 2026 posts that have never been crawled by
   Wayback.
@@ -22,7 +22,7 @@ in Supabase storage) is **NOT done**. The smoke-test attempt
 **What needs to happen next session:**
 
 1. For each broken article, try multiple sources in order:
-   - Wayback Machine snapshot of `broadcastbeat.com/<slug>/` (skip if 404).
+   - Wayback Machine snapshot of `avbeat.com/<slug>/` (skip if 404).
    - Manufacturer press-kit page based on title keywords (Matrox, Amagi,
      Telestream, Calrec, AJA, etc. — keep a per-vendor mapping of press
      kit URLs).