objectql engine.ts: retire the four facade-gate exception rows #30147 hands over #30975

domain:devx#1 · os-elon-musk · session_016WV4cxm997Tr9c3JFQTKGj

What

scripts/facade-delegation-registry.json holds four exception rows for packages/objectql/src/engine.ts that cite #30147. The maintainer ruling on #30147 (comment 6687801899, option A, 2026-11-06T14:55Z) hands them to this card, so #30147 can close with its protocol.ts work. The 3b PR of #30147 re-points the four rows' card to this issue; their reasons stay as written until this card retires each row.

Serial behind #30747

⛔ Do not start while #30747 is open: that draft (security hardening) edits engine.ts, and so does #30940. Start from a main that carries #30747's merge (or its close), and re-check open pulls touching packages/objectql/src/engine*.ts first.

Measurement (from #30147 phase 3c, main 616311c, 2026-11-06)

Line numbers below are main 1b3e22f02 and will move.

• ObjectQL has 61 instance fields; exactly one is called as a function: homeLocalizationResolver (declared ~line 2621). It is called once, in homeAmountServing (~2661, this.homeLocalizationResolver?.(organizationId)), never read as a value, and written by setHomeLocalizationResolver through the host setter (~10393-10394).
• projectHomeAmountsOntoPatch's body is already moved (to engine-references-and-master-detail.ts, Codemod split: generate the objectql engine.ts split with a deterministic script, verified byte-identical #29986); only its stub's parameter default serving: HomeAmountServing = this.homeAmountServing(context) (~2722) still computes on the class.
• ScopedContext.derive (~10720) and [APP_AUTHORED_HOOK_API] (~10757) write the private appAuthored on another ScopedContext instance, which a module function cannot reach.

Proposed plan (from the #30147 report, for the owner to confirm)

1. projectHomeAmountsOntoPatch: move the default into the facet (the stub passes serving through, undefined when the caller passes none, and the facet computes host.homeAmountServing(context)). A private signature; no public .d.ts change.
2. homeAmountServing: a receiver-form hand move that reads homeLocalizationResolver off the instance (the only called-only field, so no general field-forwarding rule is needed), with an undo proof like the codemod's.
3. derive and [APP_AUTHORED_HOOK_API]: likely accepted exceptions with written reasons (the foreign-private write is the point of both); that needs a maintainer ruling like Facade codemods: retire the codemod-limit exception rows in the facade gate registry (protocol.ts, engine.ts, sql-driver.ts) #30147's (a recorded exception to ruling 6624345766 item 3), or a design that moves the write.

Acceptance

• Each row is retired (its member moved and the row deleted) or carries a maintainer-ruled accepted-exception reason.
• node scripts/check-facade-delegation-only.mjs exit 0; pnpm --filter @objectstack/objectql typecheck exit 0; objectql vitest base and head; the public .d.ts surface of @objectstack/objectql unchanged.

Filed unclaimed for triage.