feat: detect when full license text has been provided and preserve as separate field (#3450)

* feat: add full text field to syft license struct
---------
Signed-off-by: Christopher Angelo Phillips <32073428+spiffcs@users.noreply.github.com>

syft/format/syftjson/model/package.go

@@ -47,6 +47,7 @@ type licenses []License
 
 type License struct {
 	Value          string          `json:"value"`
+	FullText       string          `json:"fullText"`
 	SPDXExpression string          `json:"spdxExpression"`
 	Type           license.Type    `json:"type"`
 	URLs           []string        `json:"urls"`

syft/format/syftjson/test-fixtures/snapshot/TestDirectoryEncoder.golden

@@ -1,7 +1,7 @@
 {
  "artifacts": [
   {
-   "id": "5a2b1ae000fcb51e",
+   "id": "cf21bacaa74c8c08",
    "name": "package-1",
    "version": "1.0.1",
    "type": "python",
@@ -15,6 +15,7 @@
    "licenses": [
     {
      "value": "MIT",
+     "fullText": "",
      "spdxExpression": "MIT",
      "type": "declared",
      "urls": [],

syft/format/syftjson/test-fixtures/snapshot/TestEncodeFullJSONDocument.golden

@@ -1,7 +1,7 @@
 {
  "artifacts": [
   {
-   "id": "ad3ecac55fe1c30f",
+   "id": "783177db0211edb6",
    "name": "package-1",
    "version": "1.0.1",
    "type": "python",
@@ -15,6 +15,7 @@
    "licenses": [
     {
      "value": "MIT",
+     "fullText": "",
      "spdxExpression": "MIT",
      "type": "declared",
      "urls": [],

syft/format/syftjson/test-fixtures/snapshot/TestImageEncoder.golden

@@ -1,7 +1,7 @@
 {
  "artifacts": [
   {
-   "id": "c5cf7ac34cbca450",
+   "id": "2d8996d6f81313df",
    "name": "package-1",
    "version": "1.0.1",
    "type": "python",
@@ -16,6 +16,7 @@
    "licenses": [
     {
      "value": "MIT",
+     "fullText": "",
      "spdxExpression": "MIT",
      "type": "declared",
      "urls": [],

syft/format/syftjson/to_format_model.go

@@ -230,6 +230,7 @@ func toLicenseModel(pkgLicenses []pkg.License) (modelLicenses []model.License) {
 
 		modelLicenses = append(modelLicenses, model.License{
 			Value:          l.Value,
+			FullText:       l.FullText,
 			SPDXExpression: l.SPDXExpression,
 			Type:           l.Type,
 			URLs:           urls,