feat(issue): gh-style issue list, view, create, edit, close and reopen

issue list renders through the shared table: a context line, ID TITLE
LABELS [STATE] [KIND] AUTHOR UPDATED with relative times on a terminal,
the ID colored by state and linked, and a stable tab-separated column
set when piped; empty results say so on stderr. It gains -s -L -l -a -A
-m -S -w, @me, comma-separated label and milestone filters, and --web.

issue view, edit, close and reopen accept #N, OWNER/REPO#N and issue
URLs. Mutations report "✓ Created/Edited/Closed issue alice/x#5 (title)"
on a terminal; issue create prints the new issue's URL on stdout (also
as issue new), and close and reopen skip issues already in that state
with a ! line and take -c/--comment. issue create and edit gain the gh
short flags and singular --add-label, --remove-label, --add-assignee and
--remove-assignee (the plural names still work), and create gains --web.

The interactive create form asks for the title and body, then "What's
next?" (submit, add metadata or cancel), without a confirmation after
it; the edit form names the issue it edits. Every issue command has help
text with examples and completes its flags and issue numbers.

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

internal/terminal/issue_edit_form.go

@@ -15,6 +15,8 @@ import (
 // IssueEditFormChoices supplies current issue values and selectable options for edit.
 // Current values missing from the options stay selectable.
 type IssueEditFormChoices struct {
+	// Heading names the edited issue above the form, such as "Editing alice/x#2 (Fix login)".
+	Heading            string
 	Title, Body        string
 	Assignees          []string
 	Milestone          *IssueMilestoneChoice
@@ -60,7 +62,7 @@ func (p *FormPrompter) EditIssue(ctx context.Context, choices IssueEditFormChoic
 	for _, label := range choices.Labels {
 		fields.labels = append(fields.labels, label.ID)
 	}
-	groups := fields.groups(choices.EditBody, choices.CanPush, withCurrent(choices.AvailableAssignees, choices.Assignees...), milestones, withCurrent(choices.AvailableLabels, choices.Labels...))
+	groups := fields.groups(choices.Heading, choices.EditBody, choices.CanPush, withCurrent(choices.AvailableAssignees, choices.Assignees...), milestones, withCurrent(choices.AvailableLabels, choices.Labels...))
 	if err := p.runForm(ctx, huh.NewForm(groups...)); err != nil {
 		return IssueEditFormValues{}, err
 	}