Brain Ingest Gate — Resolve and Dedup Before Anything Enters the Brain

Convention: see conventions/brain-first.md — the lookup chain (gbrain entity → search → query → get) is the same chain this gate runs before every write.

Convention: see _brain-filing-rules.md — when the gate's verdict is "write", the primary subject picks the directory.

Convention: skills/conventions/quality.md owns the cross-cutting page rules (citations, Iron Law back-linking, notability) — every page the gate lets through follows them. Gate-specific delta: the gate only decides write/link/skip; the admitting skill applies the quality rules on write.

The Rule

No content enters the brain without passing this gate. A raw cp or mv into the brain repo is a bug.