Add thread rename support

internal/store/store_test.go

@@ -120,6 +120,44 @@ func TestListThreadsPage(t *testing.T) {
 	}
 }
 
+func TestRenameThread(t *testing.T) {
+	ctx := context.Background()
+	st, err := Open(ctx, filepath.Join(t.TempDir(), "bot.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer st.Close()
+
+	ws, err := st.AddWorkspace(ctx, t.TempDir(), "repo", true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	thread, err := st.CreateThread(ctx, 42, "codex-thread", ws.ID, "old title")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := st.RenameThread(ctx, 42, thread.ID, "new title"); err != nil {
+		t.Fatal(err)
+	}
+	thread, err = st.GetThreadByID(ctx, 42, thread.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if thread.Title != "new title" {
+		t.Fatalf("title = %q", thread.Title)
+	}
+	if err := st.RenameThreadByCodexID(ctx, "codex-thread", "codex title"); err != nil {
+		t.Fatal(err)
+	}
+	thread, err = st.GetThreadByID(ctx, 42, thread.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if thread.Title != "codex title" {
+		t.Fatalf("title = %q", thread.Title)
+	}
+}
+
 func TestValidateWorkspacePath(t *testing.T) {
 	if _, err := ValidateWorkspacePath("relative/path"); err == nil {
 		t.Fatal("relative path should be rejected")