Rollup merge of #122217 - estebank:issue-119685, r=fmease

Handle str literals written with `'` lexed as lifetime

Given `'hello world'` and `'1 str', provide a structured suggestion for a valid string literal:

```
error[E0762]: unterminated character literal
  --> $DIR/lex-bad-str-literal-as-char-3.rs:2:26
   |
LL |     println!('hello world');
   |                          ^^^^
   |
help: if you meant to write a `str` literal, use double quotes
   |
LL |     println!("hello world");
   |              ~           ~
```
```
error[E0762]: unterminated character literal
  --> $DIR/lex-bad-str-literal-as-char-1.rs:2:20
   |
LL |     println!('1 + 1');
   |                    ^^^^
   |
help: if you meant to write a `str` literal, use double quotes
   |
LL |     println!("1 + 1");
   |              ~     ~
```

Fix #119685.

compiler/rustc_parse/src/errors.rs

@@ -1987,6 +1987,17 @@ pub enum UnknownPrefixSugg {
         style = "verbose"
     )]
     Whitespace(#[primary_span] Span),
+    #[multipart_suggestion(
+        parse_suggestion_str,
+        applicability = "maybe-incorrect",
+        style = "verbose"
+    )]
+    MeantStr {
+        #[suggestion_part(code = "\"")]
+        start: Span,
+        #[suggestion_part(code = "\"")]
+        end: Span,
+    },
 }
 
 #[derive(Diagnostic)]
@@ -2198,12 +2209,21 @@ pub enum MoreThanOneCharSugg {
         ch: String,
     },
     #[suggestion(parse_use_double_quotes, code = "{sugg}", applicability = "machine-applicable")]
-    Quotes {
+    QuotesFull {
         #[primary_span]
         span: Span,
         is_byte: bool,
         sugg: String,
     },
+    #[multipart_suggestion(parse_use_double_quotes, applicability = "machine-applicable")]
+    Quotes {
+        #[suggestion_part(code = "{prefix}\"")]
+        start: Span,
+        #[suggestion_part(code = "\"")]
+        end: Span,
+        is_byte: bool,
+        prefix: &'static str,
+    },
 }
 
 #[derive(Subdiagnostic)]