feat: fit list tables to the terminal and write TSV when piped

Lists had no header, wrapped every row once a title was longer than
the terminal, and were space-padded when piped, so cut -f and awk -F'\t'
could not split them and empty cells collapsed.

terminal.Table now takes column specs and a Display. On a terminal it
prints an uppercase header, aligns columns two spaces apart and shrinks
flexible columns, widest first, to Streams.Width (the terminal, then
$COLUMNS, then 80), cutting by display width with "…". States use the
terminal's ANSI 16 colors, hex colors fall back to the 256-color palette
unless COLORTERM advertises 24-bit, and OSC 8 links appear only on the
first column, independently of color (TEA_HYPERLINKS=auto|always|never).
Piped tables are tab-separated without header, color or links, and times
are RFC3339 UTC instead of "about 2 hours ago".

terminal.View lays out single resources (title, badges, metadata, fields,
body, footer URL) and renders markdown bodies with glamour on a terminal
only (TEA_MARKDOWN=raw keeps them raw). Shared formatters cover relative
times, timestamps, sizes, durations and status icons.

In the app, writeTable and writeView are the new list and view writers:
a "Showing N of M …" context line, an empty-state message on stderr and
the next-page hint. writeList, writeItem and batch keep working and now
render through the new table: tab-separated when piped, truncated at the
widest column on a terminal, with headers for issue list and pr list.

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

internal/terminal/format.go

@@ -0,0 +1,55 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package terminal
+
+import (
+	"fmt"
+	"time"
+)
+
+// Bytes formats a size in binary units: "13 B", "2.9 MiB".
+func Bytes(n int64) string {
+	if n < 1024 {
+		return fmt.Sprintf("%d B", n)
+	}
+	units := []string{"KiB", "MiB", "GiB", "TiB"}
+	value, unit := float64(n)/1024, 0
+	for value >= 1024 && unit < len(units)-1 {
+		value /= 1024
+		unit++
+	}
+	return fmt.Sprintf("%.1f %s", value, units[unit])
+}
+
+// Duration formats an elapsed time by its two largest units: "1h 30m", "1m 12s", "45s".
+func Duration(d time.Duration) string {
+	d = d.Round(time.Second)
+	hours, minutes, seconds := int(d/time.Hour), int(d%time.Hour/time.Minute), int(d%time.Minute/time.Second)
+	switch {
+	case hours > 0:
+		return fmt.Sprintf("%dh %dm", hours, minutes)
+	case minutes > 0:
+		return fmt.Sprintf("%dm %ds", minutes, seconds)
+	default:
+		return fmt.Sprintf("%ds", seconds)
+	}
+}
+
+// StatusIcon summarizes a check or run in one cell: ✓ succeeded, X failed, - skipped or canceled, and * still
+// pending. A conclusion, when present, takes precedence over the status.
+func StatusIcon(status, conclusion string) Cell {
+	if conclusion != "" {
+		status = conclusion
+	}
+	switch status {
+	case "success":
+		return Cell{Text: "✓", Color: "green"}
+	case "failure", "error":
+		return Cell{Text: "X", Color: "red"}
+	case "cancelled", "canceled", "skipped": //nolint:misspell // Gitea API spelling.
+		return Cell{Text: "-", Muted: true}
+	default:
+		return Cell{Text: "*", Color: "yellow"}
+	}
+}