v0.1.20 — installer rebrand + os-guide cleanup + colleague-name scrub

Changed

• Installer rebrand — fork users now see "Second-Brain OS Installer" instead of "Samba Onboarding". Stale samba-onboarding-named language was leaking into the user-facing surfaces of the v0.1.19 bundle — the installer header, log file (~/samba-onboarding.log), shell-rc comment block, runtime "samba-onboarding artifacts detected" message, and the INSTALL.md troubleshooting section all referenced the company-internal install tool that fork users don't have. Renamed in 6 files: scripts/lib/ui.sh (header + subtitle + log filename), scripts/lib/prereqs.sh (shell-rc comment + stale "Installing Samba CLIs" reference), scripts/lib/verify.sh (post-install hints), scripts/install.sh (top-of-file comment + variable rename SAMBA_DONE→FOUNDATION_INSTALLED + foundation-detection message), INSTALL.md (troubleshooting section), and beru-workspace/3-Resources/templates/scripts/transcript-extract.sh (comment). Detection logic widened from gh + gws + claude to gh + claude (gws isn't shipped in this bundle).
• os-guide skill body genericized. Removed ~15 abstract decision #N and system-design.md cross-references that wouldn't resolve for fork users (the design log is maintainer-private). Skill remains operative: still routes OS-shaped questions to canonical sources, still cites with file:line refs. Dropped the "Locked design decisions" routing-table subsection entirely (was Sid-private). Replaced "After locking a new decision in system-design.md §7" with "in your fork's design log (if you keep one)". Cleaner for forkers, no functional change for the maintainer.
• Contact-skill examples genericized to placeholder names. contact/SKILL.md and contact-log/SKILL.md taught the fuzzy-match algorithm using literal Samba colleague names (Omar Zennadi / Jaya Aswani / Alyson Sprague / Bob van Toorn / Lena Kincaid / Michael Zennadi). Replaced consistently across the skill bodies with placeholder names (Alex Chen / Priya Patel / Jordan Rivera / Robin van Pelt / Lena Okoye / Michael Chen + michele anti-regression example) that preserve the algorithmic structure including the substring-vs-token anti-regression rule.
• Briefing skill body genericized. briefing/SKILL.md: 9 literal "Sid" references replaced with <user.name> or "the user"; tagline examples changed from "Omar's waiting on you" to "Alex is waiting on you"; the "Origin incident" callout that named real colleagues (Bob/Jay/Walter/Phillip group DM) replaced with the abstract "a multi-person DM thread containing the highest-leverage open question was invisible" version that preserves the technical lesson.
• External-action-guard hook message changed from "explicit Sid approval" to "explicit user approval".

Fixed

• scripts/lib/prereqs.sh install_jq comment referenced validate_oauth_json and "step 5 (Installing Samba CLIs)" — neither exists in the public bundle. Rewrote to point at the real consumers (.claude/tools/*, extract-template.sh settings-filter, MCP config parsing).

Known issues remaining (cosmetic)

• Brand-preset count in v0.1.19 CHANGELOG narrative says 72 but the actual export ships 73. Cosmetic.