refactor: consolidate legacy record_turn_memory into unified API (T90.3)

The Phase 1 single-bot ``record_turn_memory`` lingered next to the
unified ``record_turn_memory_for_present`` introduced in T84. Only test
fixtures still called the legacy entry point.

- Remove ``record_turn_memory`` from ``chat/services/memory_write.py``.
- Update the two test_memory_write.py callers to use
  ``record_turn_memory_for_present(..., guest_bot_id=None)``, which
  produces the same ``[you=1, host=1, guest=0]`` witness mask.

The unified API returns ``dict[bot_id, (event_id, memory_id)]``; tests
extract the host entry. No production callers were affected.

chat/services/memory_write.py

@@ -22,62 +22,6 @@ from sqlite3 import Connection
 from chat.eventlog.log import append_and_apply
 
 
-def record_turn_memory(
-    conn: Connection,
-    *,
-    chat_id: str,
-    host_bot_id: str,
-    narrative_text: str,
-    scene_id: int | None = None,
-    chat_clock_at: str | None = None,
-    source: str = "direct",
-    significance: int = 1,
-) -> tuple[int, int | None]:
-    """Append a ``memory_written`` event for the host bot's POV of this turn.
-
-    Uses :func:`chat.eventlog.log.append_and_apply` (not raw
-    :func:`append_event`) so the new memory row is projected immediately
-    without re-running prior non-idempotent handlers (e.g. ``edge_update``
-    deltas).
-
-    Returns ``(event_id, memory_id)``. ``event_id`` is the row id of the
-    just-appended ``memory_written`` event in ``event_log``. ``memory_id``
-    is the autoincrement PK of the corresponding ``memories`` row — these
-    are *different* numbers (event_log and memories use independent
-    rowid sequences) so callers needing to update significance or pin
-    state must use ``memory_id``. Falls back to ``None`` if the projected
-    row can't be located, which shouldn't happen but keeps the return
-    shape stable.
-    """
-    payload: dict = {
-        "owner_id": host_bot_id,
-        "chat_id": chat_id,
-        "pov_summary": narrative_text,
-        "witness_you": 1,
-        "witness_host": 1,
-        "witness_guest": 0,
-        "source": source,
-        "reliability": 1.0,
-        "significance": significance,
-        "pinned": 0,
-        "auto_pinned": 0,
-    }
-    if scene_id is not None:
-        payload["scene_id"] = scene_id
-    if chat_clock_at is not None:
-        payload["chat_clock_at"] = chat_clock_at
-
-    event_id = append_and_apply(conn, kind="memory_written", payload=payload)
-    row = conn.execute(
-        "SELECT id FROM memories "
-        "WHERE owner_id = ? AND chat_id = ? "
-        "ORDER BY id DESC LIMIT 1",
-        (host_bot_id, chat_id),
-    ).fetchone()
-    memory_id = row[0] if row else None
-    return event_id, memory_id
-
-
 def _write_one_memory(
     conn: Connection,
     *,

tests/test_memory_write.py

@@ -22,7 +22,7 @@ from chat.db.migrate import apply_migrations
 from chat.eventlog.log import append_event
 from chat.eventlog.projector import project
 from chat.llm.mock import MockLLMClient
-from chat.services.memory_write import record_turn_memory, record_turn_memory_for_present
+from chat.services.memory_write import record_turn_memory_for_present
 import chat.state.entities  # noqa: F401  - register handlers
 import chat.state.memory  # noqa: F401
 import chat.state.world  # noqa: F401
@@ -64,14 +64,19 @@ def test_record_turn_memory_writes_event_and_projects(tmp_path):
     apply_migrations(db)
     _seed_minimal(db)
     with open_db(db) as conn:
-        eid, mid = record_turn_memory(
+        # T90.3: legacy ``record_turn_memory`` was removed; the unified
+        # ``record_turn_memory_for_present`` with ``guest_bot_id=None``
+        # produces the same single-bot witness mask [1,1,0].
+        result = record_turn_memory_for_present(
             conn,
             chat_id="chat_bot_a",
             host_bot_id="bot_a",
+            guest_bot_id=None,
             narrative_text="BotA looks up. 'You're back late.'",
             scene_id=None,
             chat_clock_at="2026-04-26T20:00:00+00:00",
         )
+        eid, mid = result["bot_a"]
         assert eid > 0
         assert mid is not None and mid > 0
 
@@ -111,12 +116,15 @@ def test_record_turn_memory_omits_optional_fields(tmp_path):
     _seed_minimal(db)
     with open_db(db) as conn:
         # Call without scene_id/chat_clock_at — should default to None.
-        eid, mid = record_turn_memory(
+        # T90.3: migrated from legacy ``record_turn_memory``.
+        result = record_turn_memory_for_present(
             conn,
             chat_id="chat_bot_a",
             host_bot_id="bot_a",
+            guest_bot_id=None,
             narrative_text="A simple memory.",
         )
+        eid, mid = result["bot_a"]
         assert eid > 0
         assert mid is not None and mid > 0