feat: Pattern H — non-code dogfood (knowledge-vault) + detection (BRO-1482)

Surfaced by dogfooding bstack into a non-code repo (a research vault): the full governance + control plane install language-agnostically and the P2 gate fires, but the dogfood cookbook had no non-code entry (only tauri/nextjs/expo/rust/rest/mcp/trading), so detection fell through to "Pattern Z — Unknown" and the agent had to author the validation predicate from scratch.

Added

• references/dogfood-patterns.md — Pattern H: Knowledge vault / Document repo (NON-CODE). The dogfood pattern for repos with no build/test suite (research vaults, Obsidian graphs, ADR/decisions folders, spec libraries, manuscripts, contract repos). Ships a reference predicate (vault-check.py — required frontmatter + every [[wikilink]] resolves, wired as make check; the non-code analog of a test suite, h ⟂ U), a five-tier predicate menu (schema / cross-reference / checklist / rubric-judge / human-sign-off), the stack=knowledge-vault Dogfood Plan, and gotchas (well-formed ≠ correct; keep the predicate independent of the authoring agent).
• Detection branch (scripts/doctor.sh §13 + scripts/onboard.sh): a markdown-dominant repo with no code build manifest (entities//.obsidian//vault/ dir or ≥5 .md files) → knowledge-vault. Added a correct CODE_MANIFEST flag (a per-file loop — ls a b c returns non-zero if ANY one is missing, so it can't answer "are they all absent"). Checked last before the Pattern Z fallback so every code pattern gets first refusal; no_code_manifest keeps it from firing on a real codebase.
• Detection-algorithm pseudocode + the inline detection summary in the cookbook updated to include Pattern H.

Notes

• Primitive count unchanged (20). This widens the P11 cookbook + detection, not a new P-row.
• Validation: dogfooded on a real non-code repo (research vault → knowledge-vault; vault-check RED→GREEN) and confirmed a manifest-less code repo does not misfire. Provenance: the live non-code dogfood (bootstrap landed identically, P2 gate blocked force-push/secret exit 2).
• VERSION 0.27.1 → 0.28.0.