feat: issue creation

internal/adapter/gitea/forge.go

@@ -18,8 +18,26 @@ type Forge struct {
 }
 
 // CreateIssue implements port.Forge.
-func (f *Forge) CreateIssue(ctx context.Context, projectID string, title string, content string) error {
-	return nil
+func (f *Forge) CreateIssue(ctx context.Context, rawProjectID string, title string, body string) (string, error) {
+	projectID, err := strconv.ParseInt(rawProjectID, 10, 64)
+	if err != nil {
+		return "", errors.WithStack(err)
+	}
+
+	project, _, err := f.client.GetRepoByID(projectID)
+	if err != nil {
+		return "", errors.WithStack(err)
+	}
+
+	issue, _, err := f.client.CreateIssue(project.Owner.UserName, project.Name, gitea.CreateIssueOption{
+		Title: title,
+		Body:  body,
+	})
+	if err != nil {
+		return "", errors.WithStack(err)
+	}
+
+	return issue.HTMLURL, nil
 }
 
 // GetIssueTemplate implements port.Forge.