Adds IO suspension support to the browser WASM kernel. When the VM
hits OP_PERFORM or the CEK suspends (e.g. from import), the kernel
now handles it instead of crashing.
sx_browser.ml additions:
- make_js_suspension: creates JS object {suspended, op, request, resume}
for the platform to handle asynchronously
- handle_import_suspension: checks library registry, returns Some result
if already loaded (immediate resume), None if fetch needed
- api_load_module: catches VmSuspended, resolves imports locally if
library is loaded, returns suspension marker to JS if not
- api_load: IO-aware CEK loop using cek_step_loop/cek_suspended?/
cek_resume — handles import suspensions during .sx file loading
This enables the lazy loading pattern: when a module's (import ...)
encounters an unloaded library, the suspension propagates to JS which
can async-fetch the .sxbc and call resume(). Currently all libraries
are pre-loaded so suspensions resolve immediately.
2608/2608 OCaml tests passing. WASM kernel builds clean.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
giles
6008a1be30