router: introduce typed ActionValidationStatus boundary (slice 5)

Introduce ActionValidationStatus enum (valid, unresolved, missing_argument,
invalid_argument, ambiguous_target) as the typed classification of validation
outcomes. ActionValidationResult now carries Status instead of boolean flags.

Backward-compatible: Unresolved() and Valid() methods preserved on the result.
Existing validation behavior unchanged: only blank Fn produces invalid_argument.
All downstream behavior (proposeGap, confirmation, task_status, praxis, hexis)
unchanged.

Tests added for all five status values, backward compatibility, and the full
validation → execution boundary.

cmd/mavend/actionresolve_test.go

@@ -385,3 +385,172 @@ func TestActExecutionFromCandidateNotSlots(t *testing.T) {
 		t.Errorf("execution from candidate replied %q; want tool success", reply)
 	}
 }
+
+// --- validation status boundary tests ---
+
+// TestActValidation_StatusValidRoute pins that a route-resolved valid action
+// produces ActionValid status and reaches execution.
+func TestActValidation_StatusValidRoute(t *testing.T) {
+	h, st := newActHandler(t)
+	ctx := context.Background()
+	now := h.now()
+
+	if err := st.EnableTool(ctx, "status", []string{"true"}, false, "test", now); err != nil {
+		t.Fatal(err)
+	}
+
+	reply := h.actionAct(ctx, router.Decision{
+		Intent:    router.IntentAct,
+		Utterance: "status",
+		Slots:     router.Slots{Fn: "status", HasFn: true},
+	})
+	if !strings.Contains(reply, "готово") {
+		t.Errorf("valid route act replied %q; want tool success", reply)
+	}
+}
+
+// TestActValidation_StatusValidMatcher pins that a matcher-resolved valid
+// action produces ActionValid status and reaches execution.
+func TestActValidation_StatusValidMatcher(t *testing.T) {
+	h, st := newActHandler(t)
+	ctx := context.Background()
+	now := h.now()
+
+	if err := st.EnableTool(ctx, "status", []string{"true"}, false, "test", now); err != nil {
+		t.Fatal(err)
+	}
+
+	reply := h.actionAct(ctx, router.Decision{
+		Intent:    router.IntentAct,
+		Utterance: "check status",
+		Slots:     router.Slots{Text: "status"},
+	})
+	if !strings.Contains(reply, "готово") {
+		t.Errorf("valid matcher act replied %q; want tool success", reply)
+	}
+}
+
+// TestActValidation_StatusUnresolved pins that an unresolved candidate
+// produces ActionUnresolved status and flows to proposeGap.
+func TestActValidation_StatusUnresolved(t *testing.T) {
+	h, st := newActHandler(t)
+	ctx := context.Background()
+	now := h.now()
+
+	if err := st.EnableTool(ctx, "status", []string{"true"}, false, "test", now); err != nil {
+		t.Fatal(err)
+	}
+
+	reply := h.actionAct(ctx, router.Decision{
+		Intent:    router.IntentAct,
+		Utterance: "deploy everything",
+		Slots:     router.Slots{Text: "deploy everything"},
+	})
+	if !strings.Contains(strings.ToLower(reply), "предлож") {
+		t.Errorf("unresolved act replied %q; want propose-gap", reply)
+	}
+}
+
+// TestActValidation_StatusInvalid pins that a structurally invalid candidate
+// produces ActionInvalidArgument status and refuses execution.
+func TestActValidation_StatusInvalid(t *testing.T) {
+	h, st := newActHandler(t)
+	ctx := context.Background()
+	now := h.now()
+
+	if err := st.EnableTool(ctx, "status", []string{"true"}, false, "test", now); err != nil {
+		t.Fatal(err)
+	}
+
+	reply := h.actionAct(ctx, router.Decision{
+		Intent:    router.IntentAct,
+		Utterance: "status",
+		Slots:     router.Slots{Fn: "  ", HasFn: true},
+	})
+	if reply == "" {
+		t.Error("expected a response for invalid candidate")
+	}
+	if strings.Contains(reply, "готово") {
+		t.Error("invalid candidate should not reach tool execution")
+	}
+}
+
+// TestActValidation_DestructiveValidStatus pins that a destructive but
+// structurally valid action still produces ActionValid status and reaches
+// the confirmation path (not validation failure).
+func TestActValidation_DestructiveValidStatus(t *testing.T) {
+	h, st := newActHandler(t)
+	ctx := context.Background()
+	now := h.now()
+
+	if err := st.EnableTool(ctx, "restart", []string{"true"}, true, "test", now); err != nil {
+		t.Fatal(err)
+	}
+
+	reply := h.actionAct(ctx, router.Decision{
+		Intent:    router.IntentAct,
+		Utterance: "restart",
+		Slots:     router.Slots{Fn: "restart", HasFn: true},
+	})
+	if !strings.Contains(reply, "да или нет") {
+		t.Errorf("destructive valid act replied %q; want confirm turn", reply)
+	}
+}
+
+// TestActValidation_ConfirmationUnchanged pins that the confirmation flow
+// is unchanged by validation.
+func TestActValidation_ConfirmationUnchanged(t *testing.T) {
+	h, st := newActHandler(t)
+	ctx := context.Background()
+	now := h.now()
+
+	if err := st.EnableTool(ctx, "restart", []string{"echo", "ok"}, true, "test", now); err != nil {
+		t.Fatal(err)
+	}
+
+	reply := h.actionAct(ctx, router.Decision{
+		Intent:    router.IntentAct,
+		Utterance: "restart nginx",
+		Slots:     router.Slots{Fn: "restart", Args: []string{"nginx"}, HasFn: true},
+	})
+	if !strings.Contains(reply, "да или нет") {
+		t.Errorf("confirmation act replied %q; want confirm turn", reply)
+	}
+}
+
+// TestActValidation_TaskStatusInterceptUnchanged pins that task_status
+// interception is unchanged by validation.
+func TestActValidation_TaskStatusInterceptUnchanged(t *testing.T) {
+	h, _ := newActHandler(t)
+	ctx := context.Background()
+
+	reply := h.actionAct(ctx, router.Decision{
+		Intent:    router.IntentAct,
+		Utterance: "task status",
+		Slots:     router.Slots{Fn: router.TaskStatusFn, HasFn: true, Text: "task status"},
+	})
+	if strings.Contains(reply, "готово") {
+		t.Errorf("task_status was not intercepted, got %q", reply)
+	}
+}
+
+// TestActValidation_NoExecutionOnFailure pins that validation failure
+// prevents downstream execution.
+func TestActValidation_NoExecutionOnFailure(t *testing.T) {
+	h, st := newActHandler(t)
+	ctx := context.Background()
+	now := h.now()
+
+	if err := st.EnableTool(ctx, "status", []string{"true"}, false, "test", now); err != nil {
+		t.Fatal(err)
+	}
+
+	reply := h.actionAct(ctx, router.Decision{
+		Intent:    router.IntentAct,
+		Utterance: "status",
+		Slots:     router.Slots{Fn: "   ", HasFn: true},
+	})
+	if strings.Contains(reply, "готово") {
+		t.Error("validation failure should not reach tool execution")
+	}
+}