v0.6.1

• Upstream sync: bump pin 7557f9e → 86f46f8 (upstream v0.6.1); reviewed all 17 commits. Provider, diagnostics, telemetry, installer/runtime packaging, generated-wiki updates, and release chores remain out of scope.
• Stop creating missing CLAUDE.md files (#933), preserve refresh rules for existing files, and conditionally stage CLAUDE.md in all four CI recipes.
• Require relative repository Markdown links and flag root-absolute hrefs (#901); retain personal-wiki root-relative links and teach Q&A to read introduction results by their exact H1 anchor (#952).
• Require atomic .last-update.json replacement for repository and personal runs, including no-op and failure paths (#840); preserve the first accepted plan after a conflicting submission (#906).
• Report repository pages with code-derived front matter or missing descriptions without failing validation (#902), refresh rechecked evidence line ranges (#936), and recognize the pi provenance actor (#897).
• Apply repository shell restrictions to research and Q&A (#888), retaining explicitly scoped host-side lifecycle bookkeeping as an adaptation and updating unattended-run guidance.