refactor: load settings once per run and reuse shared helpers

The application caches the settings snapshot and reloads it only after
an update through the store, so output and prompt helpers no longer
read and parse config.yml and hosts.yml several times per command.
canPrompt and chooser replace the inline prompt-policy checks.

Checks are tallied by one services.Tally, terminal.Plural replaces the
two app copies, refKind.article/noun replace the comment group's own
words, list commands use servicePage, and web URLs are built by
repositoryURL and webURL in browser.go.

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

internal/app/issue_attachments.go

@@ -45,8 +45,8 @@ func attachmentView(item services.IssueAttachment) terminal.View {
 
 func (a *application) issueAttachmentCommand(kind refKind) *cobra.Command {
 	words := commentWords(kind)
-	group := &cobra.Command{Use: "attachment", Short: "Manage the attachments of " + words.noun + "s", Long: fmt.Sprintf(`List, view, upload, download, rename and delete the files attached to %s. Attachments
-are addressed by the %s number and the attachment ID that attachment list shows.`, article(words.noun), words.noun)}
+	group := &cobra.Command{Use: "attachment", Short: "Manage the attachments of " + kind.noun() + "s", Long: fmt.Sprintf(`List, view, upload, download, rename and delete the files attached to %s. Attachments
+are addressed by the %s number and the attachment ID that attachment list shows.`, kind.article(), kind.noun())}
 	annotations := map[string]string{"tea.arguments": words.arguments}
 	// discussionTarget resolves the issue or pull request argument of an attachment command.
 	discussionTarget := func(cmd *cobra.Command, raw string) (target, int64, error) {