v1.0.1 — first-run & recovery fixes

Patch release — first-run and recovery fixes from launch-week field reports. No feature or behavior changes beyond the installers.

Fixed

• Install failed on stock Macs with !! python3 >= 3.11 required (reported by our first field tester 🎉). macOS resolves python3 to the Xcode CLT build (often 3.9) even when a modern Python is installed. Both install.sh and bootstrap.sh now hunt for python3.13 / python3.12 / python3.11 before settling for python3, and the error — when it does fire — prints the version found plus the exact brew / apt command to fix it. The README Quick start now states the prerequisite above the one-liner.
• Moving the repo directory broke the install unrecoverably. Both installers checked for the presence of their artifacts (Stop hook, cr/sb rc blocks) rather than their correctness, so re-running them didn't repair stale absolute paths. They now repoint stale entries — foreign hooks and unmanaged rc content preserved — making the documented recovery (./install.sh && ./bin/install-cr.sh from the new location) actually work. Covered by new regression tests that simulate the move under an isolated HOME.

Docs

• New README section on AI summaries/topics: enriching your existing history is opt-in (sb refresh --enrich) since it spends your plan's quota; new sessions are summarized automatically by the nightly job (only summary-less sessions are ever sent).
• docs/SETUP.md: install flags are now a table with explanations.

Full changelog: v1.0.0...v1.0.1