Capability primitives promoted from mcp_tree.ml to sx_primitives.ml:
- with-capabilities — push cap set, eval body, restore on exit/error
- current-capabilities — returns active capability list (nil = unrestricted)
- has-capability? — check if capability granted (true when unrestricted)
- require-capability! — raise if capability missing
- capability-restricted? — check if any restrictions active
Infrastructure: _cek_call_ref in sx_types.ml (forward ref pattern)
allows primitives to invoke the CEK evaluator without dependency cycles.
10 new tests: unrestricted defaults, scoping, nesting, restore-on-exit.
2693 total tests, 0 regressions.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
giles
5df21fca36