x-pack-otel plugin follow-up tasks

[gregkalapos]

https://github.com/elastic/elasticsearch/pull/111091 introduced the otel-data plugin. That PR moved a few things to core to enable sharing across apm-data and otel-data and defined the initial mappings for otel-data.

otel-data is currently by default disabled because it's in an early stage.

This issue is to track follow-up adjustment which we'd like to make.

• [ ] Move ignore_malformed to metrics@settings https://github.com/elastic/elasticsearch/pull/111091#discussion_r1705083085
• [ ] Add tests that tests that verify the consistency of the different index template https://github.com/elastic/elasticsearch/pull/111091#discussion_r1705429315
• [ ] Enabling LogsDB https://github.com/elastic/elasticsearch/pull/111091#discussion_r1705176620 - Initial commit done in https://github.com/elastic/elasticsearch/issues/111877, but we may add more index.sort.field fields. See: https://github.com/elastic/elasticsearch/pull/111091#discussion_r1716413660
• [ ] Cover metrics mappings with tests: https://github.com/elastic/elasticsearch/pull/114042#discussion_r1787408686
• [ ] Add index.mapping.ignore_malformed: true to a the central place used by all signals: https://github.com/elastic/elasticsearch/pull/114856#discussion_r1802544560

[elasticsearchmachine]

Pinging @elastic/es-data-management (Team:Data Management)