Update MSRV to 1.85, and edition=2024 (#201)

Required for an egui update

Author: emilk

.github/workflows/rust.yml

@@ -94,7 +94,7 @@ jobs:
       - uses: actions-rs/toolchain@v1
         with:
           profile: minimal
-          toolchain: 1.81.0
+          toolchain: 1.85.0
           target: wasm32-unknown-unknown
           override: true
       - name: Download and install Trunk binary