Suggest similar names for types, macros and modules

[Zoybean]

Given the following code: Playground link

fn main() {
    let s = string::new();
    let s = Str::new();
}

The current output is:

error[E0433]: failed to resolve: use of undeclared crate or module `string`
 --> src/main.rs:2:13
  |
2 |     let s = string::new();
  |             ^^^^^^ use of undeclared crate or module `string`

error[E0433]: failed to resolve: use of undeclared type `Str`
 --> src/main.rs:3:13
  |
3 |     let s = Str::new();
  |             ^^^ use of undeclared type `Str`

Some errors have detailed explanations: E0433.
For more information about an error, try `rustc --explain E0433`.
error: could not compile `sandbox` due to 2 previous errors

Ideally the output should look like:

error[E0433]: failed to resolve: use of undeclared crate or module `string`
 --> src/main.rs:2:13
  |
2 |     let s = string::new();
  |             ^^^^^^ use of undeclared crate or module `string`
  |
help: there is a type with a similar name (notice the capitalization)
  |
2 |     let s = String::new();
  |             ~~~~~~
help: there is a type with a similar name
  |
3 |     let s = str::new();
  |             ~~~

error[E0433]: failed to resolve: use of undeclared type `Str`
 --> src/main.rs:3:13
  |
3 |     let s = Str::new();
  |             ^^^ use of undeclared type `Str`
help: there is a type with a similar name (notice the capitalization)
  |
3 |     let s = str::new();
  |             ~~~
help: there is a type with a similar name
  |
2 |     let s = String::new();
  |             ~~~~~~

Some errors have detailed explanations: E0433.
For more information about an error, try `rustc --explain E0433`.
error: could not compile `sandbox` due to 2 previous errors

Currently, when a crate, function, method, or enum variant is not found, similar-named items will be shown as hints. However, when a type, module, or macro is misspelled, the same kind of hints are not shown. I particularly think mistakes involving capitalisation should be considered. This issue came about with a friend I was introducing to rust, and I was hoping the compiler would suggest correcting string to String.

[Zoybean]

Potentially related issues: #95462, #48676

[m-ysk]

@rustbot claim