cerebro-rust-migration

# Cerebro Rust Migration Authority cutover is family-by-family and fails closed. Before editing, read [docs/engineering/rust-organizational-platform.md](../../../docs/engineering/rust-organizational-platform.md) (authority model, compatibility port, remaining-callers table) and [docs/engineering/rust-graph-read-migration-plan.md](../../../docs/engineering/rust-graph-read-migration-plan.md) (sequencing and capability gaps). ## Invariants that gate every change - A persisted `(tenant, source, family)` authority record selects exactly one writer, including replay/refetch/device/CLI/orchestrator entry points. Do not add alternate Go entry points that could restore a retired writer. - Rust authority requires a commit receipt and fails closed. The compatibility mapper is parity evidence, never a write fallback for a promoted family. - Promotion is driven by stored parity receipts: `cerebro-platform evaluate-family` evaluates, `promote-family` records authority, `show-authority` reads the effective record. ## Porting a compatibility caller 1. Find the caller's row in the remaining-callers table; it names the exact Rust read-API capability gap blocking it. 2. Map the caller's entity kinds and relations into the organizational schema before touching query code; path callers additionally need URN-keyed `FindPaths` entry points. 3. Migrated callers must stop referencing `ports.RawCypherQueryStore` — that reference is what marks a caller as legacy. 4. Update the remaining-callers table in the same PR. ## Parity and validation - `make fixture-oracle-generate` regenerates the checked Go fixture oracle consumed by Rust parity tests. - `make projection-parity-test` compares legacy and Rust semantic projection facts over the same provider records. - Focused Rust loop: `make rust-fmt-check rust-clippy rust-test`; benchmarks via `make rust-organizational-platform-benchmark` when projection cost is touched. - `make changed-check` for the diff-selected remainder. ## Public PR safety Keep tenant names, environment details, candidate counts, and rollout observations out of public PR metadata — see "Public PR Data Safety" in [AGENTS.md](../../../AGENTS.md).