build: bump to the Rust 2024 edition

Dockerfile

···
 COPY frontend .
 RUN npm run build:production
 
-FROM rust:1.83 AS builder-rs
+FROM rust:1.85 AS builder-rs
 
 WORKDIR /usr/src/myivo-server
 COPY server .

server/Cargo.toml

···
 [package]
 name = "myivo-server"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 

server/src/main.rs

···
 use askama::Template;
 use async_stream::stream;
 use axum::{
+    Router,
     extract::{Query, State},
     http::{HeaderName, HeaderValue, StatusCode},
-    response::{sse, Html, IntoResponse, Sse},
+    response::{Html, IntoResponse, Sse, sse},
     routing::{get, get_service},
-    Router,
 };
 use serde::Deserialize;
 use tokio::time::{self, MissedTickBehavior};