[BUG] @geajs/ssr: store serialization fails on symbol-keyed items; select value binding crashes linkedom shim

[mehmetfiskindal]

Describe the bug

Two independent issues break renderToString for form-heavy apps:

1. Store serialization fails with DevalueError: Cannot stringify POJOs with symbolic keys

The keyed-list runtime stamps bookkeeping symbols directly onto raw store items (Symbol.for('gea.d.dirty'), and a Symbol('gea.itemKey')-keyed Set on parents) via the reactive proxy set trap. After rendering, serializeStores() walks the live proxied store tree with devalue's uneval(), which refuses POJOs that have symbolic own properties:

[gea-ssr] Render error: DevalueError: Cannot stringify POJOs with symbolic keys
    at walk (devalue/src/uneval.js:122)
    at serializeStores (@geajs/ssr/dist/chunk-KDLSDZE2.js:441)
  path: '.cvStore.data.education[0]'

Any SSR app whose rendered output includes a keyed .map() over store arrays hits this on every request.

Suggested fix: sanitize symbol-keyed own properties (deep clone keeping only string keys / values devalue supports) before calling uneval() in serializeStores.

2. <select value={...}> crashes under the linkedom shim

@geajs/ssr uses linkedom as its DOM shim, but linkedom's HTMLSelectElement declares value as a getter-only property. The compiler emits el.value = ... writes for value bindings, which throw in strict mode:

TypeError: Cannot set property value of [object Object] which has only a getter

Repro: render any component containing <select value={someStoreValue} ...> during SSR.

Suggested fix: in installDom(), define a value setter on the shimmed select prototype that updates the matching option's selected flag (linkedom's HTMLOptionElement.selected setter already handles deselecting siblings).

Affected versions

@geajs/ssr@1.0.4, @geajs/core@1.4.0, @geajs/vite-plugin@1.4.1

Workarounds we applied locally

• Sanitize symbol keys before uneval() in serializeStores
• Patch linkedom's HTMLSelectElement.prototype.value with a setter before rendering

Happy to send PRs for both if you'd like.