refactor(bootstrap): migrate default decks to seed file

Extracts /deck/info's default_deck_list into seeds/default-decks.json
via the new extract-default-decks.ps1 PowerShell script and imports
through DefaultDeckImporter. The importer carries the same orphan-
card-id warning the old GlobalsImporter path emitted; production cards
yield 0 orphans. WarnOrphans stays inside GlobalsImporter for now —
SpotCards/ReprintedCards/UnlimitedRestrictions/LoadingExclusionCards
still use it until Task 9.

Part of the bootstrap seed refactor (Task 6).

SVSim.Bootstrap/Program.cs

@@ -90,6 +90,8 @@ public static class Program
             await mypage.ImportMasterPointRankingPeriodAsync(context, opts.SeedDir);
             await mypage.ImportSpecialDeckFormatsAsync(context, opts.SeedDir);
 
+            await new DefaultDeckImporter().ImportAsync(context, opts.SeedDir);
+
             // BuildDeck pipeline: series CSV → catalog JSON → package CSV. Catalog must run after
             // series CSV (FK on products → series) and before package CSV (so the catalog-side
             // enriched rows take precedence over stub creation).