fix(projection): the title is derived too

Retiring the displaced rows left `cust-wp-0010` and `kont-wp-0013` correctly
identified and correctly backed while describing a different workplan's work:
the update path syncs status, backing path and commit, but never title. I had
said it would repair the title; it did not.

Seven rows fleet-wide carry a title differing from their file, and three of them
are why a blanket sync would be wrong: activity-core's files parse to an empty
title, and blanking a real one is worse than leaving it stale. The sync applies
only when the derived title is non-empty, which makes it four real corrections.

The `_Row` fixture carried no `title` attribute at all, so no existing test
could have caught this. Added, with the new tests written against the fake
session rather than as assertions on source text.

755 pass.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 2583210@bnt-lap001
Assistant-Session: f2bff2d5-e9b2-4338-92ca-10282a927006

tests/test_forge_projection.py

@@ -198,11 +198,15 @@ class _Repo:
 
 
 class _Row:
-    def __init__(self, slug, status, path):
+    def __init__(self, slug, status, path, title=None):
         import uuid as _u
         self.id = _u.uuid4()
         self.slug = slug
         self.status = status
+        # The title is a derived field the reset syncs; the fixture carried no
+        # `title` at all, so it could not have caught the drift that left
+        # cust-wp-0010 describing another workplan's work.
+        self.title = title
         self.backing_relative_path = path
         self.backing_filename = path.rsplit("/", 1)[-1]
         self.backing_archived = False
@@ -979,3 +983,50 @@ class TestCompetingClaims:
         assert src.index("UUID_MATCH, SLUG_MATCH, PATH_MATCH, PREFIX_MATCH = 0, 1, 2, 3") > 0
         # Strength is ordered strongest-first, so a lower number wins.
         assert "if strength < held:" in src
+
+
+class TestTitleIsDerivedToo:
+    """The title is a derived field and must follow the file.
+
+    Not syncing it left `cust-wp-0010` correctly identified and correctly backed
+    while describing a different workplan's work.
+    """
+
+    def test_title_is_synced(self):
+        import inspect
+        src = inspect.getsource(fp.reset_repository_projection)
+        assert "row.title = w.title.strip()" in src
+
+    def test_an_empty_derived_title_does_not_blank_a_real_one(self):
+        """Three activity-core files parse to no title; blanking is worse than stale."""
+        import inspect
+        src = inspect.getsource(fp.reset_repository_projection)
+        i = src.index("row.title = w.title.strip()")
+        guard = src[max(0, i - 200):i]
+        assert "w.title and w.title.strip()" in guard
+
+
+class TestTitleSyncBehaviour:
+    """Exercised against the fake session rather than asserted on source."""
+
+    @pytest.mark.asyncio
+    async def test_a_drifted_title_is_corrected(self):
+        row = _Row(slug="demo-wp-0001", status="active",
+                   path="workplans/a.md", title="Some Other Workplan")
+        session = _FakeSession(repo=_Repo(), rows=[row])
+        out = await fp.reset_repository_projection(
+            session, "demo",
+            derived=TestReset()._derived(("DEMO-WP-0001", "active", "workplans/a.md")),
+        )
+        assert out.status == "applied"
+        assert row.title != "Some Other Workplan"
+
+    @pytest.mark.asyncio
+    async def test_an_empty_derived_title_leaves_the_existing_one(self):
+        row = _Row(slug="demo-wp-0001", status="active",
+                   path="workplans/a.md", title="Real Title")
+        d = TestReset()._derived(("DEMO-WP-0001", "active", "workplans/a.md"))
+        d.workplans[0].title = None
+        session = _FakeSession(repo=_Repo(), rows=[row])
+        await fp.reset_repository_projection(session, "demo", derived=d)
+        assert row.title == "Real Title"