C2Rust fails to translate valid scalar initializer list for `double` (`Init list not implemented for Double`)

[chisa22]

C2Rust fails to transpile a valid C program that initializes a double using a braced scalar initializer.
In C, scalar initialization with braces is valid, and the following program should be accepted.
Reproducer

int main(void) {
    double x = { 0.0 };
    return 0;
}

Observed Behavior
C2Rust fails during translation with:

error: Failed to translate main: Init list not implemented for Double

It also still emits an incomplete Rust file:

pub fn main() {
    unsafe { ::std::process::exit(main_0() as i32) }
}

where main_0 is missing.
Environment

• c2rust version: v0.21.0
• platform: Ubuntu 24.04
• Rust: nightly-2022-08-08
• Clang version: 17.0.6