docs: place upstream in a subtree and settle the LINA link declaration

[thisisjun786]

Summary

Settles how SION holds its ClawSweeper base and how its LINA link is declared, so Stage 1 can start.

• Source layout (docs/design/sion.md): the upstream ClawSweeper tree sits under upstream/ as a git subtree. Upstream files keep their content and relative paths; the repository root (README, LICENSE, AGENTS.md, CONTRIBUTING.md, .github/) belongs to SION. Upstream workflows under upstream/.github/workflows/ never run here, because GitHub runs workflows only from the root. Operator workflows are placed by SION's installation and call SION's root reusable workflows, which run upstream code from upstream/. An upstream sync uses git subtree merge --prefix upstream and merges with a merge commit.
• CI (docs/policy/ci.md): new "Upstream tree" section. The upstream job uses Node 24 from upstream's engines, pnpm from packageManager through corepack, pnpm install --frozen-lockfile and pnpm run check in upstream/.
• Dependencies (docs/policy/dependencies.md, new): upstream's manifest, lockfile and workspace settings are used as upstream ships them and change only through a sync. Packages that only SION's own code uses follow SION's rules: exact registry versions, a committed frozen lockfile, no install scripts, and no minimum release age.
• LINA link: result fields now come only from the SION section of LINA's host protocol. Every result carries the check state. The declaration is outbox/declaration.json on state, with the product version, protocol versions, capabilities and the targets whose link is on. Connecting is a person naming the operator repository in LINA. Mailbox file paths follow LINA's schema and fixtures.
• Upstream behavior: the operator-repository visibility rule and the dashboard's public-only view are marked as upstream behavior. The dashboard no longer refuses to publish. When it leaves private targets out, it shows that on the page and records it on state.
• Checks permission: stage permissions follow what upstream's jobs request. Upstream reads check runs and commit statuses and publishes no Check Runs, so no stage writes checks.
• AGENTS.md: design contracts are described in the present tense.

Verification

• Checked against ClawSweeper at c73bf38: 35 workflows exist only under .github/workflows/, and the only workflow_call ones are internal. setup-pnpm takes a working-directory, and no upstream code uses git rev-parse --show-toplevel. Every target token mints permission-checks: read, and the README says the retired commit-review lane no longer publishes Check Runs. The public dashboard projection never returns private repositories, and the scheduler doc keeps fanout public-only unless records publish to a private state surface.
• node .github/scripts/check-docs.mjs passes. So do node --test .github/scripts/*.test.mjs and git diff --cached --check.
• Anchors #source-layout, #types and ci.md#upstream-tree, plus the LINA anchors host-protocol.md#sion and integrations.md#sion-link, were checked by reading. No other document links to a changed sion.md section.

🤖 Generated with Claude Code

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[chatgpt-codex-connector]

Codex Review Summary

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Review	Status	Commit	Review trigger
🔒 Security Review	✅ Completed 2026-10-01T17:18:01.254783Z	4883c1f	PR opened

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[devin-ai-integration]

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