refactor: reuse the existing service and rendering helpers

services.IsNotFound replaces the hand-rolled 404 checks, convertPage
the copied page conversions and lastPathNumber the comment's own
number parser. The List wrappers around ListPage of releases,
branches, wiki pages, secrets and variables go, pull request filters
resolve milestones through Milestones.FindOne like issues, and
localFlagsChanged, boolOrder, Cell.Render, stateBadge and dueText
replace their copies.

Signed-off-by: bircni <bircni@icloud.com>

internal/services/metadata.go

@@ -58,7 +58,7 @@ func (s Labels) ListPage(ctx context.Context, limit, page int) (Page[Label], err
 		labels, resp, err := s.list(ctx, limit, page)
 		return labels, headerOf(resp), err
 	})
-	return Page[Label]{Items: convertAll(labels.Items, labelFrom), More: labels.More, Total: labels.Total, Counted: labels.Counted}, err
+	return convertPage(labels, labelFrom), err
 }
 
 func (s Labels) list(ctx context.Context, limit, page int) ([]*gitea.Label, *gitea.Response, error) {
@@ -218,7 +218,7 @@ func (s Milestones) ListPage(ctx context.Context, state string, limit, page int)
 		})
 		return milestones, headerOf(resp), err
 	})
-	return Page[Milestone]{Items: convertAll(milestones.Items, milestoneFrom), More: milestones.More, Total: milestones.Total, Counted: milestones.Counted}, err
+	return convertPage(milestones, milestoneFrom), err
 }
 
 // Create creates one milestone.