Put work items in the state store, and bind the log to them (M1.1)

Development Plan M1.1, as discussed.

- Schema v4: a work_items table (id, scope, title, status, outcome,
  position, data) and an agent row whose active_item points at one
  (NULL: idle). Canonical events and intents carry their work item, and
  events their actor. Older stores are refused with a clear message:
  there was no production data, so no migration (the mechanism stays).
- The log is reached through a Transcript bound to one work item and
  one actor: store.transcript(item, actor) reads only that item and
  writes with both. The planner, executor, delegation and expert desk
  get one per call from the orchestrator instead of holding the store,
  so a component can neither read another task's events (the planner
  read every earlier task's, #78) nor write without attribution.
  store.all_events() is kept for readers that span items (evaluation
  capture, dumps). Intents are begun through the transcript or with
  work_item=, so each belongs to its item.
- The orchestrator opens a work item on 'use', closes it with its
  outcome (completed or abandoned), and carries what the operator said
  while idle into the new item as copies with their origin, so a task
  sent before 'use' is still planned from (D1). control.py keeps its
  state machine through get_state()/transition(), now over the active
  work item, until M2.6 retires it.
- nisse_dev.dump shows work items and each event's item and actor.

Tests: test_work_items.py (scoping, attribution, intent ownership,
restart, outcomes, carried messages, a second task never seeing the
first); the suites updated for the per-call transcript.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPQ14L3LikyefCMFBqEbKE

nisse-dev/tests/test_canonical.py

@@ -16,7 +16,7 @@ from nisse_dev.canonical import (
     from_payload,
     mint_call_id,
 )
-from nisse_dev.state import CURRENT_SCHEMA_VERSION, StateStore
+from nisse_dev.state import StateSchemaError, StateStore
 
 ALL_EVENTS = [
     UserMessage(text="use demo", source="matrix:$abc"),
@@ -45,18 +45,20 @@ ALL_EVENTS = [
 def test_all_event_types_round_trip(tmp_path: Path) -> None:
     with StateStore(tmp_path / "state.db") as store:
         for event in ALL_EVENTS:
-            store.append_event(event)
+            store.transcript("t", "executor").append(event)
     with StateStore(tmp_path / "state.db") as store:
-        stored = store.read_events()
+        stored = store.transcript("t", "executor").read()
     assert [s.event for s in stored] == ALL_EVENTS
     assert [s.id for s in stored] == sorted(s.id for s in stored)
+    assert {(s.work_item, s.actor) for s in stored} == {("t", "executor")}
 
 
 def test_read_events_after_id(tmp_path: Path) -> None:
     with StateStore(tmp_path / "state.db") as store:
-        first = store.append_event(UserMessage(text="one", source="m:1"))
-        store.append_event(UserMessage(text="two", source="m:2"))
-        tail = store.read_events(after=first)
+        log = store.transcript("t", "operator")
+        first = log.append(UserMessage(text="one", source="m:1"))
+        log.append(UserMessage(text="two", source="m:2"))
+        tail = log.read(after=first)
     assert [s.event.text for s in tail] == ["two"]
 
 
@@ -102,26 +104,17 @@ V1_SCHEMA = [
 ]
 
 
-def test_default_migration_upgrades_a_real_v1_store(tmp_path: Path) -> None:
+def test_a_store_from_before_work_items_is_refused_clearly(tmp_path: Path) -> None:
+    # No production data predates work items, so there is no migration from
+    # these versions (Development Plan M1.1): the store must say so rather
+    # than open half-understood.
     db = tmp_path / "state.db"
     conn = sqlite3.connect(db)
     for statement in V1_SCHEMA:
         conn.execute(statement)
-    conn.execute("INSERT INTO meta (key, value) VALUES ('schema_version', '1')")
-    conn.execute(
-        "INSERT INTO agent_state (id, state, project, data, updated_at) "
-        "VALUES (1, 'IDLE', NULL, '{}', 't')"
-    )
+    conn.execute("INSERT INTO meta (key, value) VALUES ('schema_version', '3')")
     conn.commit()
     conn.close()
 
-    with StateStore(db) as store:
-        assert store.schema_version == CURRENT_SCHEMA_VERSION
-        state = store.get_state()
-        assert state is not None
-        assert state.state == "IDLE"  # v1 data intact
-        store.append_event(UserMessage(text="hello", source="m:1"))
-        assert len(store.read_events()) == 1
-        # Two migrations were traversed, so both later tables must exist.
-        store.mark_outcome(1, "good", "arrived via v1 -> v3")
-        assert store.outcomes()[1] == ("good", "arrived via v1 -> v3")
+    with pytest.raises(StateSchemaError, match="predates work items"):
+        StateStore(db)