parquet_pushdown(M0): cover daemon Config validation, especially connector-trusted gating

The connector-trusted trust mode is the dev-only escape hatch and
must require both -trust=connector-trusted *and*
-dev.connector_trusted_ack. The latter is intentionally awkward to
flip so an operator cannot disable catalog validation by accident.

Add unit tests covering: default ok, port range, missing filer
addresses, connector-trusted without ack rejected, connector-trusted
with ack accepted, unknown trust modes rejected, and that the error
message names the ack flag so the operator knows how to proceed.

weed/parquet_pushdown/daemon/config_test.go

@@ -0,0 +1,76 @@
+package daemon
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/parquet_pushdown"
+	"github.com/seaweedfs/seaweedfs/weed/pb"
+)
+
+func baseConfig() Config {
+	return Config{
+		IP:             "127.0.0.1",
+		Port:           18888,
+		FilerAddresses: []pb.ServerAddress{"localhost:8888"},
+		Version:        "test",
+	}
+}
+
+func TestConfig_ValidateOK(t *testing.T) {
+	c := baseConfig()
+	if err := c.Validate(); err != nil {
+		t.Fatalf("expected ok, got %v", err)
+	}
+	if c.TrustMode != parquet_pushdown.TrustModeCatalogValidated {
+		t.Errorf("default trust mode = %q, want %q", c.TrustMode, parquet_pushdown.TrustModeCatalogValidated)
+	}
+}
+
+func TestConfig_RejectsBadPort(t *testing.T) {
+	c := baseConfig()
+	c.Port = 0
+	if err := c.Validate(); err == nil {
+		t.Fatal("expected error for port=0")
+	}
+	c.Port = 70000
+	if err := c.Validate(); err == nil {
+		t.Fatal("expected error for port>65535")
+	}
+}
+
+func TestConfig_RequiresFiler(t *testing.T) {
+	c := baseConfig()
+	c.FilerAddresses = nil
+	if err := c.Validate(); err == nil {
+		t.Fatal("expected error when filer addresses empty")
+	}
+}
+
+// Connector-trusted is dev-only and must require an explicit
+// acknowledgement flag. Operators must not be able to flip it on by
+// passing -trust=connector-trusted alone.
+func TestConfig_ConnectorTrustedRequiresAck(t *testing.T) {
+	c := baseConfig()
+	c.TrustMode = parquet_pushdown.TrustModeConnectorTrusted
+	err := c.Validate()
+	if err == nil {
+		t.Fatal("expected error when connector-trusted lacks ack")
+	}
+	if !strings.Contains(err.Error(), "connector_trusted_ack") {
+		t.Errorf("error %q should mention the ack flag", err.Error())
+	}
+
+	c.ConnectorTrustedAck = true
+	if err := c.Validate(); err != nil {
+		t.Fatalf("connector-trusted with ack should pass, got %v", err)
+	}
+}
+
+func TestConfig_RejectsUnknownTrustMode(t *testing.T) {
+	c := baseConfig()
+	c.TrustMode = parquet_pushdown.TrustMode("nonsense")
+	if err := c.Validate(); err == nil {
+		t.Fatal("expected error for unknown trust mode")
+	}
+}