Name the subject a conflict is actually about

A shared verb is not a shared fact. 「客厅的恒温器调到 22 度」 and
「卧室的恒温器调到 24 度」 agree with each other; the store had been
recording them as one thermostat moving, and the older side then left the
answer page — asking about the living room returned the bedroom's reading
as the only evidence. A conflict now requires the two memories to lead
with the same subject, and the subject is the first content word rather
than the first word, so 「The router forwards 220 packets」 still leads
with its router behind the article.

The rule trades one error for another, and both directions are measured
and pinned: a qualifier on the subject reads as a different thing, and
the first number under a label is the value that gets compared. Neither
hides a memory — each leaves a disagreement unrecorded for a person to
supersede by hand.

Six review findings, all measured before being changed:
- the archive rule string hid that an unset importance archives too
- a never-archived id reported {"restored": 1} while nothing moved
- the suppression condition (both sides in the page) was undocumented
- a determinism claim had no reproducible path, two latency numbers were
  never committed, and one cited test name did not exist

Gates: 374 passed, six acceptance files 73 passed, ruff clean, mypy cold
cache 24 errors in 9 files (the recorded 9cb46c1 baseline, net 0),
pyright 0 on the touched files, go build/vet/test + gofmt clean, npm
bundle unchanged, product audit clean, MCP smoke passing across processes.

backend/tests/test_memory_tiers.py

@@ -204,3 +204,19 @@ def test_importance_is_a_stated_value_and_not_a_free_number(tmp_path) -> None:
             holder_id="wife",
             importance=1.5,
         )
+
+
+def test_a_restore_counts_the_memories_it_brought_back_and_only_those(tmp_path) -> None:
+    service, database = _service(tmp_path)
+    settings = Settings(home=tmp_path, default_holder="wife")
+    retrieval = RetrievalService(settings=settings, database=database)
+    archived = _remember(service, "我们的钥匙放在玄关抽屉里")
+    standing = _remember(service, "恒温器设定 22 度", importance=0.9)
+
+    service.archive_stale(older_than_days=0, at=NOW + timedelta(days=365), max_importance=0.5)
+
+    assert service.restore([archived]) == 1
+    assert [hit.atom.atom_id for hit in retrieval.search("钥匙", filters=SearchFilters(as_holder="wife")).hits] == [archived]
+    assert service.restore([standing, archived]) == 0, (
+        "a memory that was never archived, or came back already, changed nothing and says so"
+    )