ui: show total scan time in the card snapshots list

Each snapshot row now renders '(N files, scanned in X.XX sec)' when the
snapshot has timing data (profilerSnapshotCountLabel); old/imported
snapshots without timing keep the plain '(N files)'. RU wording 'за X.XX
сек'. SW cache v100 -> v101.

frontend/sw.js

@@ -1,4 +1,4 @@
-const CACHE = 'otaman-v100';
+const CACHE = 'otaman-v101';
 const URLS = [
   'index.html',
   'help.html',