Changelog: an Upgrading section for 0.2.1 and entries checked against the code

[renmengye]

Prepares [Unreleased] for 0.2.1 without bumping the version. Each entry was checked against git diff dc994d5..HEAD.

• Removes the messaging and local-GPU paragraphs that 0.2.0 already shipped.
• Adds the ### Upgrading section RELEASING.md now requires: no contract change; research-log created on first publish; check an existing research-log for a stale ledger and run migrate-ledger if needed, with --force only after looking; let open agent PRs finish before upgrading; restart local loops.
• Splits the Claude-model change into three precise Breaking entries: when OUTERLOOP_CLAUDE_MODEL is required, how panel lenses inherit, and that the verify Action skips with a successful exit when no model is configured (a fix for that is on the queue).
• States plainly that full init currently requires a Claude model even for a non-Claude deployment.

Docs only.

🤖 Generated with Claude Code

[github-actions]

Round 1 — reviewed head ec08e731 — reviewer summarizer:hermes/gpt-5.6-terra over coverage+credentials+deployment+general+lifecycle+prose.

terra
Advisory findings from outerloop — the code owner decides. Reply to disagree; the outerloop:no-review label opts this PR out.

Verdict: nothing blocking — 1 advisory note.

1 finding attached to the lines below.

One merged non-blocking finding: deployment, lifecycle, and prose agree that the stale-ledger dry-run command must include --force. Rejected: coverage’s line-14 claim is overbroad because the documented recovery specifically targets an existing stale ledger, where --force is required; general’s contrary dry-run claim conflicts with the stale-ledger preflight behavior corroborated by deployment and lifecycle.