client: track key source, print when used

to avoid confusing messages about using encryption keys when restoring
plaintext backups, or about loading master keys when they are not
actually used for the current operation.

Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>

src/bin/proxmox_backup_client/snapshot.rs

@@ -239,7 +239,7 @@ async fn upload_log(param: Value) -> Result<Value, Error> {
     let crypt_config = match crypto.enc_key {
         None => None,
         Some(key) => {
-            let (key, _created, _) = decrypt_key(&key, &crate::key::get_encryption_key_password)?;
+            let (key, _created, _) = decrypt_key(&key.key, &crate::key::get_encryption_key_password)?;
             let crypt_config = CryptConfig::new(key)?;
             Some(Arc::new(crypt_config))
         }