Don't fail migrations if an invalid object is encountered, but tag object as invalid

1. Tag objects as “invalid” if they cause an exception when being migrated, but don’t fail the entire migration.
2. Log an error message informing administrators that there are invalid objects which require inspection. For each invalid object, provide an error stack trace to aid in debugging.
3. Administrators should be able to generate a migration report (similar to the one dry run migrations create) which is an NDJSON export of all objects tagged as “invalid”.
4. When an invalid object is read the Saved Objects client will throw an invalid object exception which should include a link to documentation to help administrators resolve migration bugs.
5. Educate Kibana developers to no longer simply write back an unmigrated document if an exception occurred. A migration should either successfully transform the object or throw.

Part of #52202