fix(audit): address /code-review findings

- scheduler _run_changed: count a run as "changed" only on a truthy NUMERIC
  value — status-string no-op dicts like {"skipped":"disabled"} (Plex off, the
  default) or {"skipped":"no demo account"} were flooding the trail every interval.
- audit.record: truncate target_id to the column width (128) like summary[:255],
  so an over-long target (e.g. a 128+ char demo email) can't abort the mutation
  the audit row is committed alongside.
- config set/reset: redact URL userinfo (user:pass@) from logged non-secret
  values — a proxy setting can embed credentials that shouldn't land in the trail.
- config set: skip the audit row when a non-secret value didn't actually change
  (no-op re-save shouldn't add noise); secrets are write-only so always logged.
- audit page title (pageMeta): add the missing "audit" case so the browser tab
  reads "Audit log · Siftlode" instead of falling back to "Feed".

backend/app/scheduler.py

@@ -130,11 +130,14 @@ def _notify_done(db, actor_id: int, job_id: str, status: str, summary: str | Non
 
 
 def _run_changed(result) -> bool:
-    """Did an automatic job run actually do something worth an audit row? (No-op polls don't.)"""
+    """Did an automatic job run actually do something worth an audit row? (No-op polls don't.)
+    A "change" = a truthy NUMERIC count; status-string dicts like {"skipped": "disabled"} (Plex
+    off — the default) or {"skipped": "no demo account"} are no-ops, not changes, so they don't
+    flood the trail every interval."""
     if result is None:
         return False
     if isinstance(result, dict):
-        return any(bool(v) for v in result.values())
+        return any(isinstance(v, (int, float)) and v for v in result.values())
     if isinstance(result, (int, float)):
         return result != 0
     return bool(result)