refactor: add terminal output and forms package (#1124)

- `internal/terminal`: streams and the prompting policy, interactive forms (issue, PR, review, merge, milestone), editor / pager / browser launching, JSON and `--jq` output.
- An aligned table renderer and a record renderer for human output; both strip control and escape characters from server-supplied text so titles and bodies cannot inject terminal sequences.

Reviewed-on: https://gitea.com/gitea/tea/pulls/1124
Reviewed-by: TheFox0x7 <95654+thefox0x7@noreply.gitea.com>

internal/terminal/table_test.go

@@ -0,0 +1,71 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package terminal
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestTable(t *testing.T) {
+	for _, tc := range []struct {
+		name  string
+		rows  [][]Cell
+		color bool
+		want  string
+	}{
+		{"empty", nil, false, ""},
+		{"aligns columns", [][]Cell{Row("7", "Fix login", "open"), Row("12", "Crash", "closed")}, false, "7   Fix login  open\n12  Crash      closed\n"},
+		{"counts runes, not bytes", [][]Cell{Row("1", "äöü", "x"), Row("2", "abcd", "y")}, false, "1  äöü   x\n2  abcd  y\n"},
+		{"counts wide runes twice", [][]Cell{Row("1", "修复", "x"), Row("2", "abcd", "y")}, false, "1  修复  x\n2  abcd  y\n"},
+		{"trims empty trailing cells", [][]Cell{Row("1", "bug", ""), Row("22", "feature", "new work")}, false, "1   bug\n22  feature  new work\n"},
+		{"pads ragged rows", [][]Cell{Row("1"), Row("2", "two")}, false, "1\n2  two\n"},
+		{
+			"strips hostile title",
+			[][]Cell{Row("1", "a\x1b]52;c;cHduZWQ=\x07b\x1b[2J\u009b31m‮txt.exe\r\ntail\tend", "open")},
+			false,
+			"1  a]52;c;cHduZWQ=b[2J31mtxt.exe tail end  open\n",
+		},
+		{"ignores styles without color", [][]Cell{{{Text: "7", Link: "https://example.org/7"}, {Text: "bug", Color: "ff0000"}, {Text: "open", Bold: true}}}, false, "7  bug  open\n"},
+		{
+			"styles after alignment",
+			[][]Cell{{{Text: "7", Link: "https://example.org/7"}, {Text: "bug", Color: "ff0000"}, {Text: "open", Bold: true}}, Row("12", "feature", "closed")},
+			true,
+			"\x1b]8;;https://example.org/7\x1b\\7\x1b]8;;\x1b\\   \x1b[38;2;255;0;0mbug\x1b[0m      \x1b[1mopen\x1b[0m\n12  feature  closed\n",
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			require.Equal(t, tc.want, Table(tc.rows, tc.color))
+		})
+	}
+}
+
+func TestRecord(t *testing.T) {
+	record := Record{
+		Heading: []Cell{{Text: "#7", Bold: true}, {Text: "Crash\x1b[2J\nnow"}, {Text: "bob\u202e"}},
+		Lines:   []string{"Steps:\r\n\x1b]52;c;aGk=\x07run\n", "https://example.org/7"},
+	}
+	require.Equal(t, "#7 Crash[2J now bob\nSteps:\n]52;c;aGk=run\n\nhttps://example.org/7\n", record.Render(false))
+	require.Equal(t, "\x1b[1m#7\x1b[0m Crash[2J now bob\nSteps:\n]52;c;aGk=run\n\nhttps://example.org/7\n", record.Render(true))
+}
+
+func TestSafeText(t *testing.T) {
+	for _, tc := range []struct{ name, in, text, line string }{
+		{"plain", "fix login", "fix login", "fix login"},
+		{"keeps tabs and line breaks", "a\tb\r\nc\nd", "a\tb\nc\nd", "a b c d"},
+		{"drops lone carriage returns", "safe\rFAKE", "safeFAKE", "safeFAKE"},
+		{
+			"strips hostile body",
+			"Steps:\r\n\x1b]52;c;cHduZWQ=\x07run\x1b[2J\u009b31m\u202e\u200bit\x7f\n\x00done",
+			"Steps:\n]52;c;cHduZWQ=run[2J31mit\ndone",
+			"Steps: ]52;c;cHduZWQ=run[2J31mit done",
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			require.Equal(t, tc.text, SafeText(tc.in))
+			require.Equal(t, tc.line, SafeLine(tc.in))
+		})
+	}
+}