Function renderFieldSvelte

Dispatch a single field through the Svelte dispatch chain.

Looks up the matching SvelteRenderFunction in the supplied resolver (with the headless resolver as fallback), invokes it with the per-field props, and returns the resulting SvelteRenderDescriptor for the parent renderer to mount.

Widget overrides (.meta({ component: name })) are resolved against the supplied instance → context → global chain before the resolver. The dispatch order matches the React adapter exactly:

1. Depth cap (MAX_RENDER_DEPTH) — returns the recursion sentinel descriptor.
2. Widget override — instance map → context map → global registry.
3. Resolver render function for tree.type.
4. Fallback — emits an em-dash / stringified-value descriptor.