docs: restructure flat docs to link to site-owned facts

[replygirl]

Summary

• docs/apply-archive.md, validation.md, schemas.md, stores.md, blocking-changes.md, harness-integration.md, and architecture.md no longer restate rule tables, exit-code tables, artifact matrices, and command semantics that apps/docs (cospec.aligned.team) now owns — each keeps its repo-internal/contributor-facing content and links out to the owning site page.
• docs/eval.md, docs/self-hosting.md, and docs/release.md were audited; no site-owned duplication found, left unchanged.
• Verified CLAUDE.md / .agents/shared.md references to docs/architecture.md and docs/stores.md still resolve correctly.
• apps/docs content is untouched.

Per-file summary

file	kept	linked out
apply-archive.md	"gate enforced twice" rationale, sync-blockers/core/blockers.ts pointer	exit codes, step order, JSON shape → /concepts/apply-and-archive
validation.md	rule-family composition/delegation logic	full rule registry → /reference/validation-rules
schemas.md	canon file pointers, matrix-parity test, requires graph, fork/init refusal mechanics	artifact matrix, Surfaces block, per-type rationale → /concepts/types-and-artifacts, /concepts/verification
stores.md	Root internals (base/cwd/store args)	setup, resolution order, context/workset → /concepts/stores
blocking-changes.md	entry-grammar regex, core/blockers.ts pointer	template, sync diagnostics prose → /concepts/blocking-changes
harness-integration.md	per-workflow behavior descriptions, managed-file writeManaged pseudocode	file tree, smoke checklist → /guide/harness-setup
architecture.md	wrapped-call discipline, static-matrix invariant, module map, archive gate ordering	failure-mode intro → /concepts/how-it-relates-to-openspec

Deviations

• None from the requested process; branched from main at 7087826, avoided touching the same lines PR docs: fix stale publish/version claims, add mise install docs #28 (still unmerged) touches in docs/release.md/docs/harness-integration.md.

Test plan

• mise run check (lint, typecheck, format, unit/contract/integration/release tests, generate:check, agents:check, schema validate) — all green
• cospec validate flat-docs-ownership --strict — pass
• cospec apply / cospec archive — gate clear, archived cleanly, blockers fanned out
• Grepped all docs/*.md relative links — all resolve

🤖 Generated with Claude Code

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