fix(project): exempt cdn_channel consumers from released-source validation; review polish

- Extend ValidateLayout exemption so cdn_channel consumers skip root/include/
  derive/manifest requirements (they resolve entirely from Source.* at runtime).
- Add TestValidateLayoutAcceptsCDNChannelConsumerWithoutReleasedSourceFields.
- Fix inverted precedence comment in CDN-base resolution block (autogen.go:325).
- Add broken-YAML subtest to TestResolveCDNChannelHardFail.
- Add assumption comment to autogenConsumerManagedLockKeyMatcher re folder_name+preserve.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/project/project_test.go

@@ -1425,6 +1425,51 @@ func TestValidateLayoutRejectsInvalidAccessoryVisualeffectsNamingConfig(t *testi
 	}
 }
 
+func TestValidateLayoutAcceptsCDNChannelConsumerWithoutReleasedSourceFields(t *testing.T) {
+	// cdn_channel consumers resolve entirely from Source.* at runtime; they must
+	// not be required to supply root/include/derive/manifest fields.
+	root := t.TempDir()
+	mkdirAll(t, filepath.Join(root, "src"))
+	mkdirAll(t, filepath.Join(root, "build"))
+
+	proj := &Project{
+		Root: root,
+		Config: Config{
+			Module: ModuleConfig{Name: "Test", ResRef: "test"},
+			Paths:  PathConfig{Source: "src", Build: "build"},
+			Autogen: AutogenConfig{
+				Consumers: []AutogenConsumerConfig{
+					{
+						ID:       "accessory_visualeffects",
+						Producer: "accessory_visualeffects",
+						Dataset:  "visualeffects",
+						Mode:     "accessory_visualeffects",
+						Optional: true,
+						AccessoryVisualeffects: AccessoryVisualeffectsConfig{
+							Groups: map[string]AccessoryVisualeffectGroupConfig{
+								"head_accessories":  {Prefix: "head_acc_"},
+								"chest_accessories": {Prefix: "chest_acc_"},
+								"head_decorations":  {Prefix: "head_dec_"},
+								"head_features":     {Prefix: "head_feat_"},
+							},
+						},
+						Source: AutogenSourceConfig{
+							Kind:         "cdn_channel",
+							ChannelsPath: "releases/haks/channels.json",
+							ManifestPath: "releases/haks/{tag}/vfxs.yml",
+						},
+						// Intentionally omitted: Root, Include, Derive, Manifest
+					},
+				},
+			},
+		},
+	}
+
+	if err := proj.ValidateLayout(); err != nil {
+		t.Fatalf("cdn_channel consumer should pass ValidateLayout without released-source fields, got: %v", err)
+	}
+}
+
 func TestLoadRejectsLegacyAccessoryVisualeffectsNamingFields(t *testing.T) {
 	root := t.TempDir()
 	writeProjectFile(t, filepath.Join(root, ConfigFile), `