When compiling Rust project with meson, dependencies' features are not fully resolved

[fre3dm4n]

Describe the bug
Rust project can have optional dependency, which will also declare a feature for this crate automatically.

For example, the Cargo.toml for a crate named dep can be like:

[package]
name = "dep"
version = "0.1.0"
edition = "2021"

[dependencies]
serde = { version = "1.0.204", optional = true }

[features]
# no need to declare serde as a feature cause cargo help us with it
# serde = ["serde"]

And for using the dep crate together the serde dependency of it, simply do:

dep = { path = "dep", features = ["serde"] }

However, currently in the meson build system, the serde won't be identified as a feature of the dep crate.

To Reproduce
The repository to reproduce

The toml feature for the figment crate is not identified.

Expected behavior
The feature can be automatically identified and exposed to meson build system.

system parameters

• Is this a cross build or just a plain native build (for the same computer)?: plain native build.
• what operating system (e.g. MacOS Catalina, Windows 10, CentOS 8.0, Ubuntu 18.04, etc.): all platform
• what Python version are you using e.g. 3.8.0: >3.11
• what meson --version: from master branch, 1.5.99
• what ninja --version if it's a Ninja build: 1.10.1