Add `/history-archive` path for history archive endpoint and document it

[leighmcculloch]

What problem does your feature solve?

The history archive in local mode is currently accessible at /archive, which is ambiguous. The term "archive" could refer to:

1. History archive - the ledger history archive produced by stellar-core
2. State archival - the protocol feature for archiving contract state
3. Metadata store - the SEP-54 data store, called in that document the "Ledger Metadata Storage," that I've heard be called a "meta lake," also being added to quickstart, which resembles a meta archive

The current /archive path doesn't clearly identify which of these it serves. We should use the full and specific name, "history archive" to make it unambiguous this is the history archive endpoint.

What would you like to see?

1. Add a new /history-archive path that clearly identifies this as the history archive endpoint
2. Keep the existing /archive path for backwards compatibility (used by stellar snapshot command)
3. Document the history archive path in the README's HTTP APIs section, noting it's only available in local mode

The /archive endpoint was never documented in the README, so there are likely very few users relying on this path. This makes it a good opportunity to introduce the clearer /history-archive path going forward. Since the endpoint was never documented, this change would also be a good time to add it to the README.

What alternatives are there?

Retain the existing /archive URL path, which isn't a big problem but leaves the ambiguity in place.

[leighmcculloch]

We've confirmed now that the metadata store won't be referred to as an archive in quickstart, so this is not an issue.

• Add galexie service for local ledger meta store #870 (comment)