Reviewer feedback on the rebased PR:
* docs/dev/writes.md residuals matrix: drop demoted methods from the trait-surface table (now `pub(crate)`); keep only the two genuine trait-surface residuals (`delete_where`, `create_vector_index`); reframe under MR-A (Lance v7.x bump) per docs/dev/lance.md.
* tests/forbidden_apis.rs: update transitional allow-list header to (a) drop the truncate_table mislabel (truncate_table is a Lance Dataset method, not a TableStore method — overwrite_batch's internal call), (b) reframe trait-surface residuals under MR-A / Lance #6666.
* crates/omnigraph/src/storage_layer.rs::SnapshotHandle::{into_arc, into_dataset}: add single-ref invariant doc — both consume Arc via try_unwrap-or-clone; sibling SnapshotHandle clones across an await point force a deep Dataset clone.
* Replace lance-4.0.0 version refs with lance-6.0.1 in active source/test/dev-doc comments (storage_layer.rs, table_store.rs, table_ops.rs, schema_apply.rs, merge.rs, recovery.rs, staged_writes.rs, consistency.rs, docs/dev/execution.md, docs/user/query-language.md). Historical refs in docs/releases/v0.4.1.md and the canonical "Lance 4.0.0 → 6.0.1 migration" line in docs/dev/lance.md left intact.
No engine code changes.
The Run state machine was removed in MR-771 (v0.4.0); `docs/dev/runs.md`
and `crates/omnigraph/tests/runs.rs` have since documented and tested the
direct-publish write path, so the "runs" name was misleading.
- git mv docs/dev/runs.md → docs/dev/writes.md (reframe H1 + intro;
keep MR-771 history note)
- git mv crates/omnigraph/tests/runs.rs → tests/writes.rs (reframe header)
- repoint every runs.md / runs.rs reference across docs, AGENTS.md, and
source comments
- fix four pre-existing broken `docs/runs.md` links (the file never lived
at that path) to `docs/dev/writes.md`
- fix the stale v0.4.0 anchor to the live section
No behavior change: every source edit is a comment. Engine builds and the
renamed test passes 25/25; scripts/check-agents-md.sh passes.
The run-removal cleanup itself (run_registry.rs guard, __run__ prefix) is
deferred to MR-770.
