Rust-analyzer shows an error when using negative numeric constants in BSN macros

## Bevy version and features

Latest main (https://github.com/bevyengine/bevy/commit/638c5dd29778c9ea718d44996b4832ed600c0169)

## What you did

```rust
#[derive(Component, Clone, Copy, Default)]
pub struct MyComponent(f32);

bsn! {
MyComponent(-0.1)
}
```

## What went wrong

Received a `expected Expr` error from rust-analyzer (but compiles fine).

## Additional information

Using braces around it does work:

```rust
bsn! {
MyComponent({-0.3})
}
```

Reproduce the issue with the provided Component and bsn! snippets in rust-analyzer, comparing the negative numeric constant with the braced form. Trace how BSN macro input is interpreted around MyComponent(-0.1); done means rust-analyzer accepts the unbraced form without an error while the example continues to compile.

Written by the indexing model from the issue text.