chore: gitignore backend/.env.cyclone-edifabric

The operator-supplied Edifabric API key file was untracked (and
showed up in 'git status' as an untracked file). Add both the
basename and the full path to .gitignore so the secret key never
gets accidentally committed.

.gitignore

@@ -34,6 +34,10 @@ ingest/
 .env
 .env.local
 .env.*.local
+# Edifabric / EdiNation operator-supplied dev key (env file).
+# Lives at backend/.env.cyclone-edifabric; source it in the shell.
+.env.cyclone-edifabric
+backend/.env.cyclone-edifabric
 
 # Production data (handled by ops, not committed)
 docs/prodfiles/*/