Error recovery doesn't work correctly when LAC is on

[Piotr Siupa]

Hello!
I've encountered a problem that I have no idea how to solve and it
doesn't seem that anyone on Stack Overflow knows anything either
(https://stackoverflow.com/q/75809021/3052438) so I came here, to the
source.

I've found that I can write a very simple grammar with error recovery
which works perfectly as long as I don't use `%define parse.lac full`.
If I do, error recovery stops working in certain cases.
Here is an example that just expects each line to be a single
character 'x' with optionally the first line being '!'. The error
recovery is supposed to resume from an EOL.

```
%{
    #include <stdio.h>
    int yylex();
    void yyerror(const char *);
%}

%define parse.lac full
%define parse.error detailed

%%

prog:
      init statements { printf("program finished successfully!\n"); }
    ;

init:
      %empty
    | '!' '\n' { printf("an optional \"special\" first line\n"); }
    ;

statements:
      %empty
    | statements 'x' '\n' { printf("correct line\n"); }
    | statements error '\n' { yyerrok; printf("error line\n"); }
    ;

%%

int yylex()
{
    char c;
    if (scanf("%c", &c) != EOF)
        return c;
    else
        return YYEOF;
}

void yyerror(const char *s) {
    fprintf(stderr, "%s\n", s);
}

int main() {
    return yyparse();
}
```

Here is what it print when I pass 2 illegal lines without LAC turned on:
```
syntax error, unexpected invalid token, expecting end of file or 'x'
error line
syntax error, unexpected invalid token, expecting end of file or 'x'
error line
program finished successfully!
```
This is what I'm expecting but the error message misses the character
`!`. LAC is supposed to fix such problems. However, if I turn it on,
the output is just:
```
syntax error, unexpected invalid token, expecting end of file or '!' or 'x'
```
So, it generates the correct message now but it doesn't enter error
recovery at all.

I have no idea if this is some kind of a bug or if I'm doing it wrong.
Any help will be appreciated.

the-example.y
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