need to show help for `adding an explicit lifetime bound`.

Code

struct Foo<'a, K: 'a = i32>(&'static T, &'static K);
fn main() {}

Current output

error[E0412]: cannot find type `T` in this scope
  --> ./src/main.rs:43:38
   |
43 | struct Foo<'a, K: 'a = i32>(&'static T, &'static K);
   |                -                     ^
   |                |
   |                similarly named type parameter `K` defined here
   |
help: a type parameter with a similar name exists
   |
43 | struct Foo<'a, K: 'a = i32>(&'static K, &'static K);
   |                                      ~
help: you might be missing a type parameter
   |
43 | struct Foo<'a, K: 'a, T = i32>(&'static T, &'static K);
   |                     +++

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0412`.

Desired output

error[E0412]: cannot find type `T` in this scope
  --> ./src/main.rs:43:38
   |
43 | struct Foo<'a, K: 'a = i32>(&'static T, &'static K);
   |                -                     ^
   |                |
   |                similarly named type parameter `K` defined here
   |
help: a type parameter with a similar name exists
   |
43 | struct Foo<'a, K: 'a = i32>(&'static K, &'static K);
   |                                      ~
help: you might be missing a type parameter
   |
43 | struct Foo<'a, K: 'a = i32, T: 'static>(&'static T, &'static K);
   |
help: consider adding an explicit lifetime bound
   |
43 | struct Foo<'a, K: 'a + 'static = i32>(&'static T, &'static K);
   |                      +++++++++

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0412`.

Rationale and extra context

No response

Other cases

No response

Rust Version

rustc 1.80.0-nightly (ef0027897 2024-05-12)
binary: rustc
commit-hash: ef0027897d2e9014766fb47dce9ddbb925d2f540
commit-date: 2024-05-12
host: aarch64-apple-darwin
release: 1.80.0-nightly
LLVM version: 18.1.4

Anything else?

No response

Reproduce the E0412 diagnostic with the Rust snippet in ./src/main.rs using the reported rustc version, then trace the compiler diagnostic that produces the missing-type-parameter suggestions. Done means the output also includes the explicit lifetime-bound suggestion shown in the desired output, without losing the existing suggestions.