[squad:plan] Echo Bloom — Docs & Narrative

**Owner:** Verbal (DevRel / Docs)

Workstream deliverables:
- World framing and lore for the greenhouse setting
- In-chamber text and onboarding copy
- Store page and demo marketing copy

Part of the Echo Bloom game plan (#54786).

Start with the Echo Bloom game plan in #54786 and review the three deliverables listed here. Done means completing the greenhouse world framing and lore, in-chamber and onboarding copy, and store page and demo marketing copy; no files or tests are named.

Written by the indexing model from the issue text.