sync: SEO canonical URLs, curation improvements, batch scripts, stats fix

- Dynamic canonical URLs and alternates for all pages (SEO fix)
- Shared seo.ts utility for canonical path generation
- Improved duplicate detection: standalone > aggregator priority, forks/created_at tie-breakers
- browseReadyFilter now includes unique aggregator skills
- Stats aligned with browseReadyFilter (was showing 16k instead of 62k+)
- Re-review mechanism: content_hash changes trigger needs-re-review
- review_status field added to skills schema
- Batch security scan and quality score scripts
- Indexer Dockerfile updated for curation deps
- Removed roadmap from README

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/app/api/stats/route.ts

@@ -34,8 +34,8 @@ export async function GET(request: NextRequest) {
       });
     }
 
-    // Browse-ready filter: exclude duplicates and aggregators
-    const browseReady = sql`${skills.isDuplicate} = false AND (${skills.skillType} IS NULL OR ${skills.skillType} != 'aggregator')`;
+    // Browse-ready filter: exclude duplicates (matches browseReadyFilter in queries.ts)
+    const browseReady = sql`${skills.isDuplicate} = false`;
 
     // Browse-ready skill stats (skills count + contributors)
     const statsResult = await db