642 - SL5b-V1 — Holon space membership

[nphias]

Summary

Every published lineage acquires OwnedBy → current HolonSpace; commit materializes the Owns
inverse on the space. Membership is queryable by ordinary traversal. GetAllHolons is untouched
— it still reads AllHolonNodes. No consumer-visible behavior change.

Changes

File	Change
commit_functions.rs	stage_space_membership, called from commit_holon's ForCreate arm after persist_holon so the new lineage's id is available to the self-ownership guard. Warns rather than skipping silently when no space is bound.
staged.rs	RelationshipCommitScope::FullExceptMembership + setter, so a version-producing commit doesn't re-anchor membership; OwnedBy ordered first under Full so a failing user relationship can't preempt it.
inverse_resolution.rs	OwnedBy → Owns short-circuit. resolve_inverse goes through the source's DescribedBy, which undescribed holons and the first core-schema load don't have.
guest_holon_service.rs	retract_space_membership on delete. Reader left on AllHolonNodes — the repoint is V2.
execution_reference.rs	assert_saved_content_eq treats OwnedBy as infrastructure-supplied, not fixture-authored.
harness (test_steps, adders, dance_tests, 2 new files)	VerifySpaceMembership step + executor + space_membership_fixture.

Tests

space_membership_fixture asserts create, independent clone, and delete — exact member keys, both
directions (Owns on the space, OwnedBy back to it). Confirmed to fail with the stamp disabled.

Full npm run sweetest exit 0: 63 tests, 0 failed, 2 ignored, audit passed. holons_core 315.
All three workspace checks clean.

Self-containment check passes: zero churn in the count fixtures, constants.rs, or any
contract/SDK/TDL doc. All of that is V2.

Three notes

1. Version leg deferred. Staging a new version stages Predecessor, whose inverse resolves
   through DescribedBy — so version-producing commits need a described holon, and this fixture
   is deliberately schema-free. add_verify_space_membership_count_step exists for schema-backed
   fixtures; wiring it into stage_new_version_fixture would close this. The staged.rs unit test
   covers the mechanism meanwhile.

2. Two pre-existing bugs found, not caused by V1. related_holons(Owns) on the space returns
   empty even when the link exists (inverse name, anchor has no DescribedBy); all_related_holons()
   finds it. And GetAllHolons errors after a delete, because the index still lists the deleted
   holon — the same limitation that had delete_holon_fixture's assertion commented out. V2 fixes
   the second by construction. The executor sidesteps both by deriving the space from a member's
   OwnedBy.

Open

The Owns fan-in cost is still unmeasured — every inverse link is based on the space holon, and
put_smartlink scans that base, so a 191-holon schema load is ~O(n²) tag decodes. Belongs to V1
since this is where the writes are introduced. Baseline by checking out the parent commit, not by
stashing.