FE-205: Replace Zustand usage with React Context

[kube]

🌟 What is the purpose of this PR?

This PR removes Zustand for State Management.

Zustand was only used for Editor and Simulation (SDCPNContext was already a React context given the PetriNet definition/state is outside of the component).

Performance

React Contexts are a bit slower, but not much now given React Compiler does a lot of optimization of the consumer components. We will optimize performance later when it will make sense to do it, if needed.

Simulation Speed

This PR required to do some rewrite of SimulationProvider in more React-way, and I ended up doing frame generation by batch/budgeting.

So now instead of generating one frame every 20ms (maximum of 50 frames per second), we compute as much frames as we can during 5ms, every 50ms. (10% of main thread time allocated to simulation).

This results in much faster generation speed. (~5000 frames per second in Production Machines example)

This still runs in main thread, but once we move the Simulator in a Web Worker, we will be able to dedicate a thread to Simulation, and should end up with 10x more frames (50000 frames per second).

🔍 What does this change?

• Every Context has a DEFAULT_CONTEXT_VALUE. This allows to easily isolate components and contexts for testing, without having to provide the whole context.
• Use use(Context) everywhere, without intermediary hook, to easily identify dependents.
• Each Context has two files, one for Context and one for Provider.
  The idea being to split Interface/Implementation, and possibly leverage React Contexts as a Dependency Injection mechanism.
  A Context could have multiple Providers in the future. (Will be useful for HASH simulation/live that will have to sync with server)

Pre-Merge Checklist 🚀

🚢 Has this modified a publishable library?

This PR:

• does not modify any publishable blocks or libraries, or modifications do not need publishing

📜 Does this require a change to the docs?

The changes in this PR:

• are internal and do not require a docs change

🕸️ Does this require a change to the Turbo Graph?

The changes in this PR:

• do not affect the execution graph

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[kube]

• FE-204: Improve Transitions and Arcs animation #8262
• FE-205: Replace Zustand usage with React Context #8258 👈 (View in Graphite)
• main

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[cursor]

PR Summary

State management overhaul

• Introduces EditorContext, SimulationContext, CheckerContext, and restructures SDCPNContext; adds Providers with DEFAULT_CONTEXT_VALUE
• Removes Zustand stores and tests (editor-store.ts, simulation-store.ts, simulation-store.test.ts), updates all hooks/components to use(Context)
• Drops zustand dependency and related imports; adjusts ESLint to allow react/jsx-no-constructed-context-values

Simulation execution

• Reimplements SimulationProvider to run on a timed loop with batched frames (time-budgeted ticks), plus completion notifications

Misc

• Centralizes Monaco typings to new contexts, updates panels/SDCPN view to new APIs
• Keeps Sentry error tracker provider; minor cleanup

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[augmentcode]

🤖 Augment PR Summary

Summary: This PR removes Zustand from Petrinaut and migrates editor/checker/simulation state management to plain React Context.

Changes:

• Removed the Zustand-based editor and simulation stores (and the simulation store tests)
• Introduced new context modules for SDCPN, Editor, Simulation, and Checker state
• Reworked providers to expose state+actions via Context values instead of Zustand selectors
• Updated hooks/components throughout the editor to consume state via use(Context)
• Adjusted checker logic to provide diagnostics via a dedicated CheckerContext
• Updated lint config (disabled react/jsx-no-constructed-context-values) and removed zustand from dependencies

Technical Notes: The simulation execution loop is now implemented with component state, refs, and timeouts instead of an external store; ensure the new Context defaults and lifecycle behavior match prior expectations.

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[augmentcode]

Review completed. 2 suggestions posted.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Inconsistent SDCPN read location may cause stale parameter values

Low Severity

The reset function reads getSDCPN() outside the setStateValues callback (line 361), while the nearly identical initializeParameterValuesFromDefaults function correctly reads it inside the callback (line 250). This inconsistency means reset could compute parameterValues from a stale SDCPN if the definition changes between the function call and when React processes the state update. The comment in initialize explicitly warns against this pattern: "Use functional update to ensure we see the latest state at processing time."

Additional Locations (1)

• libs/@hashintel/petrinaut/src/state/simulation-provider.tsx#L246-L260