Fix issue label deletion with Actions tokens (#37013)

Use shared repo permission resolution for Actions task users in issue
label remove and clear paths, and add a regression test for deleting
issue labels with a Gitea Actions token.

This fixes issue label deletion when the request is authenticated with a
Gitea Actions token.
Fixes #37011 

The bug was that the delete path re-resolved repository permissions
using the normal user permission helper, which does not handle Actions
task users. As a result, `DELETE
/api/v1/repos/{owner}/{repo}/issues/{index}/labels/{id}` could return
`500` for Actions tokens even though label listing and label addition
worked.

---------

Co-authored-by: Codex <codex@openai.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: Giteabot <teabot@gitea.io>

models/issues/issue_label.go

@@ -356,7 +356,7 @@ func ClearIssueLabels(ctx context.Context, issue *Issue, doer *user_model.User)
 			return err
 		}
 
-		perm, err := access_model.GetUserRepoPermission(ctx, issue.Repo, doer)
+		perm, err := access_model.GetDoerRepoPermission(ctx, issue.Repo, doer)
 		if err != nil {
 			return err
 		}

models/issues/issue_update.go

@@ -665,9 +665,9 @@ func ResolveIssueMentionsByVisibility(ctx context.Context, issue *Issue, doer *u
 			continue
 		}
 		// Normal users must have read access to the referencing issue
-		perm, err := access_model.GetUserRepoPermission(ctx, issue.Repo, user)
+		perm, err := access_model.GetIndividualUserRepoPermission(ctx, issue.Repo, user)
 		if err != nil {
-			return nil, fmt.Errorf("GetUserRepoPermission [%d]: %w", user.ID, err)
+			return nil, fmt.Errorf("GetIndividualUserRepoPermission [%d]: %w", user.ID, err)
 		}
 		if !perm.CanReadIssuesOrPulls(issue.IsPull) {
 			continue

models/issues/issue_xref.go

@@ -207,7 +207,7 @@ func (issue *Issue) verifyReferencedIssue(stdCtx context.Context, ctx *crossRefe
 
 	// Check doer permissions; set action to None if the doer can't change the destination
 	if refIssue.RepoID != ctx.OrigIssue.RepoID || ref.Action != references.XRefActionNone {
-		perm, err := access_model.GetUserRepoPermission(stdCtx, refIssue.Repo, ctx.Doer)
+		perm, err := access_model.GetDoerRepoPermission(stdCtx, refIssue.Repo, ctx.Doer)
 		if err != nil {
 			return nil, references.XRefActionNone, err
 		}

models/issues/pull_list.go

@@ -93,7 +93,7 @@ func CanMaintainerWriteToBranch(ctx context.Context, p access_model.Permission,
 			if err != nil {
 				continue
 			}
-			prPerm, err := access_model.GetUserRepoPermission(ctx, pr.BaseRepo, user)
+			prPerm, err := access_model.GetIndividualUserRepoPermission(ctx, pr.BaseRepo, user)
 			if err != nil {
 				continue
 			}

models/issues/review.go

@@ -919,7 +919,7 @@ func CanMarkConversation(ctx context.Context, issue *Issue, doer *user_model.Use
 		return false, nil
 	}
 	if doer.ID != issue.PosterID {
-		p, err := access_model.GetUserRepoPermission(ctx, issue.Repo, doer)
+		p, err := access_model.GetDoerRepoPermission(ctx, issue.Repo, doer)
 		if err != nil {
 			return false, err
 		}