log more details in debug logs like URL being accessed

### Describe the feature you'd like to request

e.g. I'm trying to setup git syncing, and even with **full** (privacy-leaking) floccus logs enabled I get only:

```
2025-11-22T11:53:36.834Z Starting sync process for account git tabs voy
2025-11-22T11:53:36.837Z onSyncStart: begin
2025-11-22T11:53:36.848Z (git) init
2025-11-22T11:53:36.864Z (git) fetch from remote
2025-11-22T11:53:36.897Z Syncing failed with HTTP Error: 404 Not Found
2025-11-22T11:53:36.897Z onSyncFail
```

on client side

### Describe the solution you'd like

It would've been extremely helpful to know ***which*** URL returned that `404` so I suggest logging that

### Describe alternatives you've considered

I've considered using some other sync method (webdav worked for me), but I'd really prefer git so I can track the changes via git log (And debug latter if I find some bookmark has disappeared etc)