feat: rust plugin rename rust keywords with trail underscore

[driftluo]

This PR Fix two bugs on molecule：

1. rust keywords on table/struct can generate code, but cannot compile with rustc, for example:

array struct [byte; 2];

struct StructP {
    type: struct
}

It is OK to name a type as a rust keyword; the rust plugin will automatically camelCase the name. However, when the field of a table/struct is named as a rust keyword, the current version does not automatically handle this problem, causing the generated code to fail to compile. This PR will automatically check the field name and add an underscore to the end of the keyword to avoid keyword conflicts.

Just like the type above, in the generated code, it will become type_(Or prefix it with r#? I'm not sure)

I think the solution to keyword conflicts must be solved in each language's plugins.

2. Since type names support uppercase and lowercase letters, they will be uniformly camel-cased. When two types have inconsistent names but consistent camel case, uncompilable code will be generated, as in the following schema:

array struct [byte; 2];

struct StructP {
    a: struct
}

union structP {
    struct,
}

This PR will detect this situation and report an error: "the name structP is used more than once, It seems that only the capitalization is inconsistent"

other change: upgrade serde_yaml/clap/pest deps

[zhangsoledad]

MSRV was bumped because of the introduction of https://doc.rust-lang.org/std/sync/struct.OnceLock.html, this should have been stated in the README