Reconcile package and example README command drift

[tonyketcham]

Source: flatbread-flow-pmf-audit.md

Project metadata

• Phase: Docs/onboarding quickstart
• Sequence: 5
• Priority: P1
• Suggested owner role: docs
• Supporting roles: DX
• Dependency status: parallelizable
• Blocked by: none

Task details

• Audit README and example command guidance for conflicting dev/start/play/codegen instructions.
• Align documented paths with the actual package and example layout.

Acceptance criteria

• No README gives conflicting guidance for dev, start, play, or codegen commands.
• Example paths and package names match the current repository layout.
• Root-level guidance points to the single recommended onboarding path.