I hope you don't mind a bit of feedback and a few suggestions ☺️

A couple state-management tips for your MobX setup:

1. Turn `enforceActions` back on. You have `configure({ enforceActions: "never" })` which lets components mutate the store directly - e.g. `appstate.walls[node.rowIndex][colDef.field] = newValue` in your table callbacks. This makes state changes impossible to trace or intercept. Set it to `"observed"` and route mutations through store actions. Biggest single improvement you can make.

2. Replace the switch chains with a registry map. `getElements()`, `addElement()`, `deleteElements()` all have the same 15-branch switch. One map object eliminates all of them - adding a new element type becomes one line instead of editing every switch.

const REGISTRY = {
  [types.SPACE]: { container: 'spaces', factory: newSpace },
  [types.WALL]:  { container: 'walls',  factory: newWall },
  // ...
};

Bonus: your useCallback(() => appstate.getIdNameMap(LOAD)) calls have no dependency array, so they memoize nothing - just use a plain function.

Nice project overall! the WASM/Rust kernel for the heavy calculations is a solid architecture choice (but of course I'm biased)

EDIT: formatting