Docs: no single guide for choosing Memory vs Knowledge (and infer + matching endpoints)

[Arpit-oo]

Problem Statement

New developers repeatedly hit the same fork in the road and there is no single page that resolves it end to end:

1. Is a piece of context a Memory or Knowledge?
2. Should infer be true or false?
3. Which ingest field and which query type belong together?
4. How do shared org knowledge and per-user memories combine?

Today the answers are spread across memories.mdx, knowledge.mdx, query.mdx, and core-concepts.mdx. Each page covers its own half well, but a developer with a concrete piece of data (a Slack thread, a PDF, a raw chat log, a stated preference) has to stitch the full journey together themselves. infer: true vs false in particular is defined in one line and easy to get wrong (it defaults to false and silently stores raw text).

Proposed Solution

Add one decision-guide page, essentials/v2/choosing-memory-vs-knowledge, registered first in the v2 Usage nav, containing:

• The single deciding question (shared vs per-user) as a two-card split.
• A decision tree (Mermaid) from 'new piece of context' to an exact ingest shape + query type.
• A routing table mapping each kind of data to store, ingest type, ingest field, infer, and query type.
• infer: true vs infer: false side by side, with the same raw signal producing two different stored memories, plus the default-false gotcha.
• Two full end-to-end paths (ingest then query) showing which endpoints pair up.
• The type: "all" merge for personalized-yet-grounded answers.
• A v1-to-v2 endpoint name map (Upload Knowledge / Add Memory / Full Recall / tenant_id ...).

Alternatives Considered

• Expanding core-concepts.mdx instead: it is a tour of five primitives and would lose focus; the decision workflow deserves its own destination page.
• A standalone infer page only: narrower, and does not fix the endpoint-pairing or store-choice confusion.

Additional Context

Submitted as part of the Mintlify x HydraDB documentation hackathon (Jul 17-24). PR to follow, referencing this issue.