chore: add workflow_dispatch trigger to scorecard

Allow manual triggering of OpenSSF Scorecard analysis.

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: Jonathan D.A. Jewell

.github/workflows/scorecard.yml

@@ -6,6 +6,7 @@ on:
     branches: [main, master]
   schedule:
     - cron: '0 4 * * 0'
+  workflow_dispatch:
 
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