categories: update SECTION_CATEGORIES map to match the AI-derived taxonomy

After the AI re-categorization, bb.wp_imported_posts.category holds the
new taxonomy: 'Industry News', 'Show Coverage', 'Cameras & Capture',
'Streaming & IP', 'Audio', 'Live Production', 'Cloud & Workflow',
'Post Production', 'Broadcast Production', 'AI & Automation'.

The map that drives /gear, /technology, /show-coverage, /news page
queries still referenced the OLD taxonomy ('Gear', 'Reviews',
'Technology', 'Streaming') — so /gear and /technology effectively
returned nothing-matched and fell through to the catch-all section,
causing the duplicate-posts-across-sections behaviour the user
reported.

  /gear         → Cameras & Capture, Audio
  /technology   → Streaming & IP, Cloud & Workflow, AI & Automation,
                  Live Production, Post Production, Broadcast Production
  /show-coverage→ Show Coverage
  /news         → Industry News

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

src/lib/articles/legacy-source.ts

@@ -74,11 +74,28 @@ const SECTION_TAGS: Record<Section, string[]> = {
   news: [],
 };
 
+// Map between site sections and the AI-derived categories now stored in
+// bb.wp_imported_posts.category. Each section query uses these to pull
+// only the relevant slice of the archive — otherwise /gear and
+// /technology would both return everything that doesn't match
+// show-coverage (the old fallback).
+//   Production-tech categories live here:
+//     "Streaming & IP", "Cloud & Workflow", "AI & Automation",
+//     "Live Production", "Post Production", "Broadcast Production"
+//   Hardware/gear:
+//     "Cameras & Capture", "Audio"
 const SECTION_CATEGORIES: Record<Section, string[]> = {
-  gear: ["Gear", "Reviews"],
-  technology: ["Technology", "Streaming", "Live Production"],
+  gear: ["Cameras & Capture", "Audio"],
+  technology: [
+    "Streaming & IP",
+    "Cloud & Workflow",
+    "AI & Automation",
+    "Live Production",
+    "Post Production",
+    "Broadcast Production",
+  ],
   "show-coverage": ["Show Coverage"],
-  news: [],
+  news: ["Industry News"],
 };
 
 function authorSlug(name: string | null): string {