Documentation: Clarify Namespace Isolation and Recall Query Limits

[sandman-sh]

Problem Description

The documentation on the MemWal repository is sparse regarding namespace partitioning. It is unclear if namespaces are cryptographically isolated or merely key-prefixed. Additionally, the behavior of the limit and query parameters on recall is not fully documented, leaving developers to guess how historical blobs are searched.

Proposed Solution

Provide detailed documentation or diagrams explaining the indexing mechanism of the memory database, namespace authorization rules, and the cost of executing semantic queries on historical states.

[github-actions]

Thank you for opening this issue, a team member will review it shortly.

[ducnmm]

Thanks for raising this, @sandman-sh! 🙏

We've received this and the team will review the documentation around namespace isolation and recall query limits. We'll improve the docs and follow up here once it's been triaged.