FE-1219: Define and enforce a Scenario HIR for server-side Petrinaut optimization

[kube]

🌟 What is the purpose of this PR?

Makes server-side Petrinaut scenario materialization go through the existing restricted HIR pipeline instead of executing manifest-authored strings via sandboxed new Function, closing the last unrestricted raw-code execution path on the optimizer's server path. The in-editor sandbox path is unchanged.

🔗 Related links

• FE-1219 — this issue
• FE-1217 — parent hardening issue

🚫 Blocked by

• FE-1220: Harden and document Petrinaut optimization execution isolation #9058 — top layer of a 3-PR stack (#9066 → #9058 → this); needs FE-1220: Harden and document Petrinaut optimization execution isolation #9058's threat-model.md and OPTIMIZATION_INTEGRATION.md

🔍 What does this change?

• petrinaut-core: two new HIR surface kinds — scenarioExpression (a single expression over (parameters, scenario) → scalar) and scenarioInit (a statement body → record of place-name → count | token records) — lowered, typechecked, and instantiated over compiler-emitted source only.
• Scenario orchestration extracted to compile-scenario-core.ts, shared by the unchanged sandboxed compileScenario (editor) and a new Node-only compileScenarioProgram (compile once per study, evaluate per trial). Exported only via the Node-only ./compiled-model subpath, so the main entry gains no TypeScript-compiler dependency.
• Scenario expressions/init compile at CLI bootstrap; out-of-subset code fails study startup with the offending manifest path. Math.random() is a compile error on scenario surfaces (determinism).
• petrinaut-cli: createOptimizationProtocol compiles the scenario program once at bootstrap; per-trial optimization.evaluate runs the pre-instantiated evaluators. No sandboxed compileScenario references remain in CLI source.
• Review fixes: rejects a const/callback parameter shadowing the scenario/parameters inputs (hir:redeclared-parameter), matching the sandbox; documents that server-compiled scenario equality is strict (==→===) and can differ from the editor for mixed-type comparisons.

Pre-Merge Checklist 🚀

🚢 Has this modified a publishable library?

This PR:

• modifies an npm-publishable library and I have added a changeset file(s)

📜 Does this require a change to the docs?

The changes in this PR:

• require changes to docs which are made as part of this PR

🕸️ Does this require a change to the Turbo Graph?

The changes in this PR:

• do not affect the execution graph

🛡 What tests cover this?

New petrinaut-core tests: a parity suite (HIR program vs sandbox for representative scenarios incl. code-mode colored tokens and the unknown-place-skip quirk), a rejection matrix (dynamic import, process, globalThis, fetch, Function, template substitution, loops, Math.random, wrapper-name shadowing), and a security test proving zero dynamic evaluation per trial. New petrinaut-cli tests: bootstrap rejection listing offending paths, compile-once-evaluate-many, and a Function-proxy test proving no per-trial dynamic evaluation.

❓ How to test this?

1. turbo run test:unit --filter '@hashintel/petrinaut-core' --filter '@hashintel/petrinaut-cli'
2. Run the CLI against examples/supply-chain-profit-optimization.json and confirm it evaluates; confirm an out-of-subset scenario manifest fails at bootstrap with the offending path in the message.

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Project	Deployment	Actions	Updated (UTC)
hash	Ready	Preview	Aug 4, 2026 8:34am
petrinaut	Ready	Preview	Aug 4, 2026 8:34am

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[cursor]

PR Summary

Medium Risk
Touches the security-critical server path for user-authored optimization manifests; risk is reduced by eliminating raw new Function on manifest text, but correctness now depends on the HIR compiler/emitters and parity with the editor sandbox for edge cases like strict equality.

Overview
Server-side scenario materialization (optimization trials and CLI scenario runs) no longer evaluates manifest strings via sandboxed new Function. Parameter overrides, per-place initial-state expressions, and code-mode initial state are lowered through new HIR surfaces (scenarioExpression, scenarioInit), typechecked, emitted, and compiled once; only compiler-emitted source is instantiated. Per trial/request, the pre-built program runs shared orchestration in compile-scenario-core.ts.

The CLI calls compileScenarioProgram at optimization study bootstrap and once per scenario run request, failing startup with manifest paths when code is outside the supported subset. The in-editor path still uses compileScenario + the existing sandbox.

HIR lowering adds scenario-specific rules (e.g. no Math.random(), no redeclaring scenario/parameters, strict equality). Docs and the optimizer threat model are updated to reflect removal of the raw server execution path.

^{Reviewed by Cursor Bugbot for commit 718ddcd. Bugbot is set up for automated code reviews on this repo. Configure here.}

[kube]

Converted back to draft: isolation (#9058) and Scenario HIR are deferred while the streaming fixes (#9057) and correlated logging (#9059) merge first to debug the staging network error. This branch still stacks on #9058 and will follow it.