Fix collection management and match some json output (#5095)

- Fixed collection management to be usable from the Password Manager UI
- Checked and brought in-to-sync with upstream several json responses
- Fixed a small issue with the `fields` response when it was empty

Signed-off-by: BlackDex <black.dex@gmail.com>

src/api/core/ciphers.rs

@@ -150,7 +150,6 @@ async fn sync(data: SyncData, headers: Headers, mut conn: DbConn) -> Json<Value>
         "ciphers": ciphers_json,
         "domains": domains_json,
         "sends": sends_json,
-        "unofficialServer": true,
         "object": "sync"
     }))
 }