Multi-line diagnostic suggestions use LF in files that use CRLF line endings

Diagnostic suggestions that include line endings only use LF line endings. However, if the file is using CRLF line endings, applying the suggestion results in a file with mixed line endings.

I would expect that suggestions should match the line-ending style of the file.

For example:

mod a {
    pub fn f() {}
}

fn main() {
    f();
}

generates JSON:

{
    "$message_type": "diagnostic",
    "message": "cannot find function `f` in this scope",
    "code":
    {
        "code": "E0425",
        "explanation": "An unresolved name was used.\n\nErroneous code examples:\n\n```compile_fail,E0425\nsomething_that_doesnt_exist::foo;\n// error: unresolved name `something_that_doesnt_exist::foo`\n\n// or:\n\ntrait Foo {\n    fn bar() {\n        Self; // error: unresolved name `Self`\n    }\n}\n\n// or:\n\nlet x = unknown_variable;  // error: unresolved name `unknown_variable`\n```\n\nPlease verify that the name wasn't misspelled and ensure that the\nidentifier being referred to is valid for the given situation. Example:\n\n```\nenum something_that_does_exist {\n    Foo,\n}\n```\n\nOr:\n\n```\nmod something_that_does_exist {\n    pub static foo : i32 = 0i32;\n}\n\nsomething_that_does_exist::foo; // ok!\n```\n\nOr:\n\n```\nlet unknown_variable = 12u32;\nlet x = unknown_variable; // ok!\n```\n\nIf the item is not defined in the current module, it must be imported using a\n`use` statement, like so:\n\n```\n# mod foo { pub fn bar() {} }\n# fn main() {\nuse foo::bar;\nbar();\n# }\n```\n\nIf the item you are importing is not defined in some super-module of the\ncurrent module, then it must also be declared as public (e.g., `pub fn`).\n"
    },
    "level": "error",
    "spans":
    [
        {
            "file_name": "main.rs",
            "byte_start": 50,
            "byte_end": 51,
            "line_start": 6,
            "line_end": 6,
            "column_start": 5,
            "column_end": 6,
            "is_primary": true,
            "text":
            [
                {
                    "text": "    f();",
                    "highlight_start": 5,
                    "highlight_end": 6
                }
            ],
            "label": "not found in this scope",
            "suggested_replacement": null,
            "suggestion_applicability": null,
            "expansion": null
        }
    ],
    "children":
    [
        {
            "message": "consider importing this function",
            "code": null,
            "level": "help",
            "spans":
            [
                {
                    "file_name": "main.rs",
                    "byte_start": 0,
                    "byte_end": 0,
                    "line_start": 1,
                    "line_end": 1,
                    "column_start": 1,
                    "column_end": 1,
                    "is_primary": true,
                    "text":
                    [],
                    "label": null,
                    "suggested_replacement": "use a::f;\n\n",
                    "suggestion_applicability": "MaybeIncorrect",
                    "expansion": null
                }
            ],
            "children":
            [],
            "rendered": null
        }
    ],
    "rendered": "error[E0425]: cannot find function `f` in this scope\n --> main.rs:6:5\n  |\n6 |     f();\n  |     ^ not found in this scope\n  |\nhelp: consider importing this function\n  |\n1 + use a::f;\n  |\n\n"
}

Notice that the suggested_replacement uses \n despite the source file using \r\n line endings.

Meta

rustc --version --verbose:

rustc 1.77.0-nightly (3cdd004e5 2023-12-29)
binary: rustc
commit-hash: [3cdd004e55c869faa2b7b25efd3becf50346e7d6](https://github.com/rust-lang/rust/commit/3cdd004e55c869faa2b7b25efd3becf50346e7d6)
commit-date: 2023-12-29
host: x86_64-pc-windows-msvc
release: 1.77.0-nightly
LLVM version: 17.0.6

Start by tracing rustc diagnostic suggestion generation using the CRLF example and the JSON suggested_replacement field shown in the report. Verify that a multi-line suggestion preserves the source file's CRLF style, and confirm the resulting diagnostic output no longer mixes line endings.