[feature] Outgoing federation of avatar/header descriptions (#4270)

Signed-off-by: nicole mikołajczyk <git@mkljczk.pl>

# Description

This implementation is compatible with Iceshrimp.NET, Pleroma and Chuckya, which already support federated avatar/header descriptions. I will add support for incoming descriptions federation in this or another PR (depending on when this one gets merged).

## Checklist

Please put an x inside each checkbox to indicate that you've read and followed it: `[ ]` -> `[x]`

If this is a documentation change, only the first checkbox must be filled (you can delete the others if you want).

- [x] I/we have read the [GoToSocial contribution guidelines](https://codeberg.org/superseriousbusiness/gotosocial/src/branch/main/CONTRIBUTING.md).
- [ ] I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
- [x] I/we have not leveraged AI to create the proposed changes.
- [x] I/we have performed a self-review of added code.
- [x] I/we have written code that is legible and maintainable by others.
- [ ] I/we have commented the added code, particularly in hard-to-understand areas.
- [ ] I/we have made any necessary changes to documentation.
- [ ] I/we have added tests that cover new code.
- [x] I/we have run tests and they pass locally with the changes.
- [x] I/we have run `go fmt ./...` and `golangci-lint run`.

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4270
Co-authored-by: nicole mikołajczyk <git@mkljczk.pl>
Co-committed-by: nicole mikołajczyk <git@mkljczk.pl>

4 files changed, 28 insertions, 2 deletions

diff --git a/internal/transport/dereference_test.go b/internal/transport/dereference_test.go
index 7d9570923..b9611d1e7 100644
--- a/internal/transport/dereference_test.go
+++ b/internal/transport/dereference_test.go
@@ -43,8 +43,8 @@ func (suite *DereferenceTestSuite) TestDerefLocalUser() {
 	defer resp.Body.Close()
 
 	suite.Equal(http.StatusOK, resp.StatusCode)
-	suite.EqualValues(1887, resp.ContentLength)
-	suite.Equal("1887", resp.Header.Get("Content-Length"))
+	suite.EqualValues(2007, resp.ContentLength)
+	suite.Equal("2007", resp.Header.Get("Content-Length"))
 	suite.Equal(apiutil.AppActivityLDJSON, resp.Header.Get("Content-Type"))
 
 	b, err := io.ReadAll(resp.Body)
@@ -77,12 +77,14 @@ func (suite *DereferenceTestSuite) TestDerefLocalUser() {
   "following": "http://localhost:8080/users/the_mighty_zork/following",
   "icon": {
     "mediaType": "image/jpeg",
+    "name": "a green goblin looking nasty",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/avatar/original/01F8MH58A357CV5K7R7TJMSH6S.jpg"
   },
   "id": "http://localhost:8080/users/the_mighty_zork",
   "image": {
     "mediaType": "image/jpeg",
+    "name": "A very old-school screenshot of the original team fortress mod for quake",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/header/original/01PFPMWK2FF0D9WMHEJHR07C3Q.jpg"
   },
diff --git a/internal/typeutils/internaltoas.go b/internal/typeutils/internaltoas.go
index 4762e3c8b..3feecaa9b 100644
--- a/internal/typeutils/internaltoas.go
+++ b/internal/typeutils/internaltoas.go
@@ -348,6 +348,12 @@ func (c *Converter) AccountToAS(
 			avatarURLProperty.AppendIRI(avatarURL)
 			iconImage.SetActivityStreamsUrl(avatarURLProperty)
 
+			if a.AvatarMediaAttachment.Description != "" {
+				nameProp := streams.NewActivityStreamsNameProperty()
+				nameProp.AppendXMLSchemaString(a.AvatarMediaAttachment.Description)
+				iconImage.SetActivityStreamsName(nameProp)
+			}
+
 			iconProperty.AppendActivityStreamsImage(iconImage)
 			accountable.SetActivityStreamsIcon(iconProperty)
 		}
@@ -382,6 +388,12 @@ func (c *Converter) AccountToAS(
 			headerURLProperty.AppendIRI(headerURL)
 			headerImage.SetActivityStreamsUrl(headerURLProperty)
 
+			if a.HeaderMediaAttachment.Description != "" {
+				nameProp := streams.NewActivityStreamsNameProperty()
+				nameProp.AppendXMLSchemaString(a.HeaderMediaAttachment.Description)
+				headerImage.SetActivityStreamsName(nameProp)
+			}
+
 			headerProperty.AppendActivityStreamsImage(headerImage)
 			accountable.SetActivityStreamsImage(headerProperty)
 		}
diff --git a/internal/typeutils/internaltoas_test.go b/internal/typeutils/internaltoas_test.go
index ab81095fd..292d7705a 100644
--- a/internal/typeutils/internaltoas_test.go
+++ b/internal/typeutils/internaltoas_test.go
@@ -66,12 +66,14 @@ func (suite *InternalToASTestSuite) TestAccountToAS() {
   "following": "http://localhost:8080/users/the_mighty_zork/following",
   "icon": {
     "mediaType": "image/jpeg",
+    "name": "a green goblin looking nasty",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/avatar/original/01F8MH58A357CV5K7R7TJMSH6S.jpg"
   },
   "id": "http://localhost:8080/users/the_mighty_zork",
   "image": {
     "mediaType": "image/jpeg",
+    "name": "A very old-school screenshot of the original team fortress mod for quake",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/header/original/01PFPMWK2FF0D9WMHEJHR07C3Q.jpg"
   },
@@ -132,12 +134,14 @@ func (suite *InternalToASTestSuite) TestAccountToASBot() {
   "following": "http://localhost:8080/users/the_mighty_zork/following",
   "icon": {
     "mediaType": "image/jpeg",
+    "name": "a green goblin looking nasty",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/avatar/original/01F8MH58A357CV5K7R7TJMSH6S.jpg"
   },
   "id": "http://localhost:8080/users/the_mighty_zork",
   "image": {
     "mediaType": "image/jpeg",
+    "name": "A very old-school screenshot of the original team fortress mod for quake",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/header/original/01PFPMWK2FF0D9WMHEJHR07C3Q.jpg"
   },
@@ -278,12 +282,14 @@ func (suite *InternalToASTestSuite) TestAccountToASAliasedAndMoved() {
   "following": "http://localhost:8080/users/the_mighty_zork/following",
   "icon": {
     "mediaType": "image/jpeg",
+    "name": "a green goblin looking nasty",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/avatar/original/01F8MH58A357CV5K7R7TJMSH6S.jpg"
   },
   "id": "http://localhost:8080/users/the_mighty_zork",
   "image": {
     "mediaType": "image/jpeg",
+    "name": "A very old-school screenshot of the original team fortress mod for quake",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/header/original/01PFPMWK2FF0D9WMHEJHR07C3Q.jpg"
   },
@@ -403,12 +409,14 @@ func (suite *InternalToASTestSuite) TestAccountToASWithEmoji() {
   "following": "http://localhost:8080/users/the_mighty_zork/following",
   "icon": {
     "mediaType": "image/jpeg",
+    "name": "a green goblin looking nasty",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/avatar/original/01F8MH58A357CV5K7R7TJMSH6S.jpg"
   },
   "id": "http://localhost:8080/users/the_mighty_zork",
   "image": {
     "mediaType": "image/jpeg",
+    "name": "A very old-school screenshot of the original team fortress mod for quake",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/header/original/01PFPMWK2FF0D9WMHEJHR07C3Q.jpg"
   },
@@ -478,12 +486,14 @@ func (suite *InternalToASTestSuite) TestAccountToASWithSharedInbox() {
   "following": "http://localhost:8080/users/the_mighty_zork/following",
   "icon": {
     "mediaType": "image/jpeg",
+    "name": "a green goblin looking nasty",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/avatar/original/01F8MH58A357CV5K7R7TJMSH6S.jpg"
   },
   "id": "http://localhost:8080/users/the_mighty_zork",
   "image": {
     "mediaType": "image/jpeg",
+    "name": "A very old-school screenshot of the original team fortress mod for quake",
     "type": "Image",
     "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/header/original/01PFPMWK2FF0D9WMHEJHR07C3Q.jpg"
   },
diff --git a/internal/typeutils/wrap_test.go b/internal/typeutils/wrap_test.go
index 48a28e3b0..828e6a683 100644
--- a/internal/typeutils/wrap_test.go
+++ b/internal/typeutils/wrap_test.go
@@ -200,12 +200,14 @@ func (suite *WrapTestSuite) TestWrapAccountableInUpdate() {
     "following": "http://localhost:8080/users/the_mighty_zork/following",
     "icon": {
       "mediaType": "image/jpeg",
+      "name": "a green goblin looking nasty",
       "type": "Image",
       "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/avatar/original/01F8MH58A357CV5K7R7TJMSH6S.jpg"
     },
     "id": "http://localhost:8080/users/the_mighty_zork",
     "image": {
       "mediaType": "image/jpeg",
+      "name": "A very old-school screenshot of the original team fortress mod for quake",
       "type": "Image",
       "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/header/original/01PFPMWK2FF0D9WMHEJHR07C3Q.jpg"
     },