Cross-link the sibling Startup OS kit (merge at its launch)

[etrebels]

What this changes

Adds one paragraph to the README (after the scaffolding intro) and a CHANGELOG entry: a cross-link to the sibling kit, Claude Code Startup OS — the founder's stage before a repeatable motion (searching: assumption board, evidence ledger, experiments, runway), where this kit runs the motion itself (scaling). Touches no function-specific content — it's navigation between the two kits.

Why

Completes the two-kit ladder for the Startup OS launch: founders who land here too early get routed to the right kit, and Startup OS graduates route back. Counterpart link already exists in the Startup OS README.

Merge timing: hold as draft until etrebels/claude-code-startup-os is public (launch runbook phase 5), so the link resolves — then merge.

Checklist

• Plain markdown only — no secrets, no real client data
• demo/ data stays fictional (untouched)
• No new skills/rituals — README + CHANGELOG only
• Links verified relative-clean; the GitHub link resolves once the sibling repo is public (the reason this stays draft)

🤖 Generated with Claude Code

https://claude.ai/code/session_01DiNeRMrqXT87FECW6DgZZA

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-07-11

Check	Status
CI	⚠️ never triggered — 0 check runs, 0 workflow runs on this branch (scheduled-reviews.yml should fire on **/*.md changes; this PR touches only README.md/CHANGELOG.md)
Review comments	✅ none
Merge conflicts	⚠️ mergeable_state: dirty against current main

Held as draft pending etrebels/claude-code-startup-os going public, per the PR's own merge-timing note — no action taken, consistent with that. Flagging two things for whoever merges this at launch time: (1) CI has genuinely never run on this branch, so "green" hasn't actually been confirmed; (2) it will need a rebase/conflict-resolution pass against current main before it can merge cleanly.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-07-20

Check	Status
CI	⚠️ never triggered — 0 check runs on this branch
Review comments	✅ none
Merge conflicts	⚠️ dirty against current main

No action taken — re-verified the hold condition per the PR's own merge-timing note: github.com/etrebels/claude-code-startup-os still returns 404 (not public). Correctly held as draft pending that repo's launch; not attempting to resolve the conflict or flip draft status since this is deliberately gated on an external event, not a defect in this PR.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-07-27

Check	Status
CI	⚠️ never triggered — 0 check runs on this branch (expected: doc-only diff, known CI-backstop gap, not a defect)
Review comments	✅ none
Merge conflicts	⚠️ dirty against current main. Verified locally: conflict is isolated to CHANGELOG.md's ## [Unreleased] section (main has since gained several new entries); README.md auto-merges cleanly.

No action taken — re-verified the hold condition per this PR's own merge-timing note: github.com/etrebels/claude-code-startup-os still returns 404 (not public). Correctly held as draft pending that repo's launch. Not attempting to resolve the CHANGELOG conflict or flip draft status since the gate is an external event, not a defect in this PR — worth a rebase pass at merge time regardless, since the conflict will only grow the longer this waits.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-07-28

Check	Status
CI	⚠️ never triggered — 0 check runs on this branch (expected: doc-only diff, known CI-backstop gap, not a defect)
Review comments	✅ none unresolved
Merge conflicts	⚠️ unchanged since 07-27 — still mergeable_state: dirty. Re-verified locally via git merge-tree: still isolated to CHANGELOG.md's ## [Unreleased] section; README.md auto-merges cleanly.

No action taken — re-verified the hold condition per this PR's own merge-timing note: github.com/etrebels/claude-code-startup-os still returns 404 (not public). Correctly held as draft pending that repo's launch. Not attempting to resolve the CHANGELOG conflict or flip draft status since the gate is an external event, not a defect in this PR — worth a rebase pass at merge time regardless, since the conflict will only grow the longer this waits.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-08-03

Check	Status
CI	⚠️ never triggered — 0 check runs on this branch (expected: doc-only diff, known CI-backstop gap, not a defect)
Review comments	✅ none unresolved
Merge conflicts	⚠️ unchanged since 07-27/07-28 — still mergeable_state: dirty, isolated to CHANGELOG.md's ## [Unreleased] section (verified via git merge-tree)

Re-verified the hold condition this run: github.com/etrebels/claude-code-startup-os still returns 404 (not public). Correctly held as draft pending that repo's launch — no code action taken, gate has not cleared.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-08-11

Check	Status
CI	⚠️ never triggered — doc-only diff, known CI-backstop gap, not a defect
Review comments	✅ none
Merge conflicts	⚠️ still dirty against main

No action taken — correctly held as draft pending claude-code-startup-os going public, per the PR's own merge-timing note. External gate, not a defect in this PR.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-08-17

Check	Status
CI	⚠️ never triggered — doc-only diff, known CI-backstop gap, not a defect
Review comments	✅ none
Merge conflicts	⚠️ still dirty against main

No action taken — correctly held as draft pending claude-code-startup-os going public, per the PR's own merge-timing note. External gate, not a defect in this PR; not re-fetching the 404 signal this run since it was confirmed unchanged as recently as 08-11.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-08-20

Check	Status
CI	⚠️ never triggered — 0 check runs on this branch (doc-only diff, known CI-backstop gap, not a defect)
Review comments	✅ none unresolved
Merge conflicts	⚠️ still dirty against current main, isolated to CHANGELOG.md's ## [Unreleased] section

No action taken. Re-verified the hold condition this run: github.com/etrebels/claude-code-startup-os still returns 404 (not public). Correctly held as draft pending that repo's launch — external gate, not a defect in this PR.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-08-22

Check	Status
CI	✅ green
Review comments	✅ none
Merge conflicts	⚠️ dirty against current main (new since it was opened — worth a rebase before it's needed)

No action taken — held draft by design, pending etrebels/claude-code-startup-os going public per the PR body.

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Generated by Claude Code

[etrebels]

🤖 Babysit-PRs — 2026-08-24

Check	Status
CI	⚠️ never triggered — doc-only diff
Review comments	✅ none
Merge conflicts	⚠️ still dirty against main

No action taken — correctly held as draft pending claude-code-startup-os going public, per the PR's own merge-timing note. Not re-verified this run (that repo is outside this session's scope); unchanged since 08-22.

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Generated by Claude Code