Cover the keep gate for unmanaged worktrees

--include-unmanaged lifts only the location gate, and nothing proved the keep
gate still held behind it.

- assert a dirty hand-made worktree survives --include-unmanaged alone

cmd/agentws/prune_test.go

@@ -746,6 +746,23 @@ func TestPruneRemovesUnmanagedWorktreeWithFlag(t *testing.T) {
 	}
 }
 
+// --include-unmanaged only lifts the location gate. A keep verdict is a separate
+// gate, so a dirty hand-made worktree still needs --include-keep to be touched.
+func TestPruneIncludeUnmanagedStillObeysKeep(t *testing.T) {
+	f := newFixture(t)
+	manual := f.addManualWorktree(t, "benvin/by-hand")
+	if err := os.WriteFile(filepath.Join(manual, "scratch.txt"), []byte("wip\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	srv := fakeGitea(t)
+	out := runOpts(t, client(srv), pruneOpts{apply: true, includeUnmanaged: true})
+	assertVerdict(t, out, "benvin/by-hand", verdictKeep, "dirty")
+	if !exists(filepath.Join(manual, "scratch.txt")) {
+		t.Error("--include-unmanaged must not remove a worktree classified keep")
+	}
+}
+
 // A worktree whose directory was deleted leaves only a registration behind:
 // there is nothing to lose, so it is prunable outright.
 func TestPruneStaleRegistrationWithMissingDirectory(t *testing.T) {