fix: reconcile the issues stream and remove the legacy output shims

Use one canPrompt and pullNumberArguments for the comment commands, set
display preferences instead of the retired environment variables in
tests, and delete writeList, writeItem, batch, table, writeRecord(s),
the legacy column map, confirm, require, validateMilestoneFlags and
listWindow now that every command uses their replacements.

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

internal/app/comments.go

@@ -4,7 +4,6 @@
 package app
 
 import (
-	"cmp"
 	"errors"
 	"fmt"
 	"strconv"
@@ -113,8 +112,8 @@ func (a *application) readComment(cmd *cobra.Command, f commentFlags, initial st
 
 // promptComment asks for a comment in the configured editor, or in a multi-line field without one.
 func (a *application) promptComment(cmd *cobra.Command, initial string) (string, terminal.Draft, error) {
-	if prompt, err := a.canPrompt(); err != nil || !prompt {
-		return "", terminal.Draft{}, cmp.Or(err, clierr.Wrap(clierr.Usage, errors.New("missing required input: supply --body, --body-file or --editor")))
+	if !a.canPrompt() {
+		return "", terminal.Draft{}, clierr.Wrap(clierr.Usage, errors.New("missing required input: supply --body, --body-file or --editor"))
 	}
 	if preferences, err := a.preferences(); err == nil && preferences.Editor != "" {
 		draft, err := a.editDraft(cmd, initial)