fix: guard against non-dict route entries when filtering Caddy routes

r.get() crashed when the Caddy API returned a routes array containing
string elements. Added isinstance(r, dict) check and also made the
match[0] traversal safer by using any() over the match list.

builder/build.sh

@@ -132,7 +132,10 @@ EOF
 import sys, json
 routes = json.load(sys.stdin)
 new_host = '${APP_ID}.${DOMAIN_SUFFIX}'
-routes = [r for r in routes if new_host not in r.get('match',[{}])[0].get('host',[])]
+routes = [r for r in routes
+          if not (isinstance(r, dict)
+                  and any(isinstance(m, dict) and new_host in m.get('host', [])
+                          for m in r.get('match', [])))]
 routes.append(json.loads(sys.argv[1]))
 print(json.dumps(routes))
 " "$ROUTE_JSON")