Add error reports info to metals doctor

[kasiaMarek]

resolves: #5672

[ckipp01]

This is a nice idea! I left a couple small comments. Since we're also changing the structure of the doctor output here we'll also want to bump the DoctorResults.version.

[jkciesluk]

Great work! I'm wondering if for reports which contain scala code in them (eg. CompilerAccess.handleError), can we wrap code in
```scala
...
```
?

[tgodzik]

Would it be possible to instead use the target name in the filename? Similar to how we do it with timestamp?

[tgodzik]

Should we bump metals to 1.1.x in this case? What do you think @ckipp01 ?

[ckipp01]

According to https://scalameta.org/metals/docs/contributors/releasing#tag-the-release probably yea.

[tgodzik]

We will also try to explain all the recent changes in a plugin authors paragraph then

[tgodzik]

Looks good, just a few comments

[tgodzik]

Suggested change

	name <- buildTargets
	.scalaTarget(buildTargetId)
	.map(_.displayName)
	.orElse(buildTargets.javaTarget(buildTargetId).map(_.displayName))
	name <- buildTargets
	.info(buildTargetId)
	.map(_.displayName))

should be enough

[tgodzik]

Could you explain a bit what this does in a comment?

[kasiaMarek]

I'm sending a timestamp but I wonder if it'd be better to send nicely formatted time-date string instead.

[tgodzik]

Looks good! Just one comment.

[tgodzik]

Suggested change

	reversed = lines.reverse
	index = reversed.indexWhere(_.startsWith(Report.summaryTitle))
	if index >= 0
	} yield reversed
	.slice(0, index)
	.reverse
	.dropWhile(_ == "")
	.map(decode)
	.mkString("\n")
	index = lines.indexWhere(_.startsWith(Report.summaryTitle))
	if index >= 0
	} yield lines
	.slice(index, lines.length)
	.takeWhile(_ != "")
	.map(decode)
	.mkString("\n")

do we need reverse at all?

[tgodzik]

You can also use lastIndexWhere if needed.