docs: revise concurrent append and replace

[317brian]

• Moves most of the concurrent append and replace stuff out of automatic compaction into its own page in the ingestion section
• Revises the steps to use the new context parameter instead of manually setting the lock type
• Hides the older but potentially still useful info about the lock types in a collapsed section

Rendered preview available here: https://druid-git-copyedit-conc-apprepl-317brian.vercel.app/docs/latest/ingestion/concurrent-append-replace

This PR has:

• been self-reviewed.

[vtlim]

Some nits. Otherwise looks good! 🦖