Document Scala compiler error codes

[WojciechMazur]

Resolves #24720

Piggy backs fixes that would be required to have correct assertions in generated scaladoc (would be most likelly cherry-picked before merge):

• allow to specific sc-opts:<scala-options>* to pass specify scalacOptions that would be passed to the snippetCompiler
• show position of snippets that failed to compile

TODO:

• - error codes 101-222
• - document 11 inactive error codes - if inactive after 3.0.0 add latest stable release emitting errors
• - setup CI assertions to ensure all snippets emit correct error - E001.md should emit only [E001] errors etc.
• - for error codes introduced after 3.0.0 add information about version when given error was introduced

[WojciechMazur]

Rendered examples:

[bishabosha]

is there an automated process to check for addition of new error codes?

[WojciechMazur]

is there an automated process to check for addition of new error codes?

Not yet but I'll add one

[tgodzik]

We could also link to these pages from DiagnosticRelatedInformation, it's available in the sbt interfaces.

[tgodzik]

Ach, no that would have to be another field, which is not exposed here :/

[tgodzik]

We could anyway link the codes in metals automatically once this is merged, which will work on all Scala 3 versions