feat: include registry.db in repo and ignore broken_paths.txt

Share the SQLite registry database so apps/analysis repos can consume
it without needing the full function tree to rebuild.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitignore

@@ -1,5 +1,4 @@
-# SQLite index (regenerable con fn index) — SOLO en raiz
-registry.db
+# SQLite index — journal/wal temporales
 registry.db-journal
 registry.db-wal
 
@@ -50,3 +49,5 @@ Thumbs.db
 
 # Archivos locales
 .local
+
+broken_paths.txt