Provide subscribers stored in global *provide-subscribers* dict (keyed
by name) instead of on provide frames. Fixes subscriber loss when
frames are reconstructed, and enables cross-cek_run notification.
Batch integration: batch-begin!/batch-end! primitives manage
*provide-batch-depth*. fire-provide-subscribers defers to queue when
depth > 0, batch-end! flushes deduped. signals.sx batch calls both.
context now prefers scope-peek over frame value — scope stack is the
source of truth since provide! always updates it (even in nested
cek_run where provide frames aren't on the kont).
2754/2768 OCaml (14 pre-existing). 32/32 WASM.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
giles
fb262aa49b