only the last disconnected session is remembered when `(ement-save-sessions)` is set to `t`

### OS/platform

Linux

### Emacs version and provenance

`GNU Emacs 30.0.50 (build 1, x86_64-gentoo-linux-musl, GTK+ Version 3.24.38, cairo version 1.18.0) of 2023-11-26 `
it comes from the official gentoo-linux repo; `emerge =app/editors-emacs`

### Emacs command

emacsclient -c

### Emacs frame type

both nox and GUI

### Ement package version and provenance

ement version 0.13; taken via straight.el from github

### Actions taken

I tried to connect to my primary account via `ement-connect`; then I eval'ed `(ement-connect :uri-prefix "http://localhost:8008")` (where 8008 is the port where pantalaimon is running on), to connect to my private account.

### Observed results

after calling `ement-disconnect` on both accounts, and re-calling `ement-connect`, it remembers only the last session I disconnected from, e.g. if I use `ement-disconnect RET account1 ement-disconnect RET account2` then `ement-connect` it will only remember the last one.

### Expected results

I swear that when I had this set up for the first time with two accounts there was a pop-up that let you choose which account to use;
the expected result is that after calling `ement-connect` it should have a prompt giving you **all** the session you've been logged

### Backtrace

_No response_

### Etc.

I tried on both doom emacs and vanilla emacs, and the result was the same; I can attach the exact same step that I did on both side if it's needed, just let me know if that would be useful.