[docs] Reconcile version/roadmap/changelog inconsistencies

[cursor]

Owner squad: @THOClabs/docs-community · Priority: P3 · Area: docs

Problem

The project's "what is done / what version are we" narrative is contradictory:

• ROADMAP.md marks v0.5.0 "Complete (January 2025)" while v0.2–v0.4 remain unchecked.
• README.md says v0.1 "Released (January 2024)".
• pyproject.toml version is 0.1.0-dev; RELEASE_v0.1.0.md also exists.

Acceptance criteria

• Establish the real current version and ship-state and make README, ROADMAP, CHANGELOG, and pyproject agree.
• Roadmap checkboxes reflect reality (don't mark later milestones complete while earlier ones are open).

Evidence

docs/reviews/2026-06-23-holistic-review.md §5.