refactor: 项目结构重组，src/ 扁平化为根目录，提取 pkg/ 子包

- 模块名重命名 yunshu -> hub.gaomia.site/titor/YunShu
- Go 版本升级 1.21 -> 1.25
- src/ 目录删除，所有文件移至根目录
- 新增 pkg/mdprint/: Markdown AST 解析+ANSI 渲染
- 新增 pkg/style/: 终端颜色样式（8色 ANSI + 24位真彩色）
- 新增 pkg/termui/: 终端输入组件（交互式输入/密码/确认）
- 更新文档：AGENTS.md、architecture.md、changelog.md、taolun.md
- gitignore 通配符修复 yunshu.exe -> yunshu.exe*

pkg/mdprint/render.go

@@ -0,0 +1,204 @@
+package mdprint
+
+import (
+	"fmt"
+	"strings"
+
+	"hub.gaomia.site/titor/YunShu/pkg/style"
+)
+
+func renderNode(node Node) string {
+	switch n := node.(type) {
+	case Heading:
+		return renderHeading(n)
+	case Paragraph:
+		return renderParagraph(n)
+	case CodeBlock:
+		return renderCodeBlock(n)
+	case Blockquote:
+		return renderBlockquote(n)
+	case List:
+		return renderList(n)
+	case Table:
+		return renderTable(n)
+	case ThematicBreak:
+		return "\n" + style.Dim.Render("────────────────────────────") + "\n"
+	case Text:
+		return style.New().Render(n.Text)
+	case Bold:
+		return renderBold(n)
+	case Italic:
+		return renderItalic(n)
+	case Code:
+		return renderInlineCode(n)
+	case Link:
+		return renderLink(n)
+	default:
+		return fmt.Sprintf("%v", n)
+	}
+}
+
+func renderInline(nodes []Node) string {
+	var b strings.Builder
+	for _, child := range nodes {
+		b.WriteString(renderNode(child))
+	}
+	return b.String()
+}
+
+var headingConfig = []struct {
+	symbol string
+	style  *style.Style
+}{
+	{"▪ ", style.New().Bold().FgHex("#6B8E9B")},
+	{"▪ ", style.New().Bold().FgHex("#89A894")},
+	{"▪ ", style.New().Bold().FgHex("#A6C0B5")},
+	{"▫ ", style.New().Bold().FgHex("#C3B1BD")},
+	{"▫ ", style.New().Bold().FgHex("#7B8E8A")},
+	{"",   style.New().Bold().Dim()},
+}
+
+func renderHeading(h Heading) string {
+	cfg := headingConfig[0]
+	if h.Level-1 < len(headingConfig) {
+		cfg = headingConfig[h.Level-1]
+	}
+	suffix := ""
+	if h.Level == 1 {
+		suffix = "\n"
+	}
+	return "\n" + cfg.style.Render(cfg.symbol+renderInline(h.Content)) + suffix
+}
+
+func renderParagraph(p Paragraph) string {
+	return renderInline(p.Content)
+}
+
+func renderCodeBlock(c CodeBlock) string {
+	var b strings.Builder
+	if c.Lang != "" {
+		b.WriteString(style.Dim.Render(c.Lang + " ") + "\n")
+	}
+	for _, line := range strings.Split(c.Body, "\n") {
+		b.WriteString("  " + style.New().Fg(style.ColorYellow).Render(line) + "\n")
+	}
+	return strings.TrimRight(b.String(), "\n")
+}
+
+func renderBlockquote(q Blockquote) string {
+	var b strings.Builder
+	for i, child := range q.Children {
+		if i > 0 {
+			b.WriteString("\n")
+		}
+		rendered := renderNode(child)
+		for _, line := range strings.Split(rendered, "\n") {
+			b.WriteString(style.Dim.Render("│ ") + line + "\n")
+		}
+	}
+	return strings.TrimRight(b.String(), "\n")
+}
+
+func renderList(l List) string {
+	var b strings.Builder
+	for i, item := range l.Items {
+		if i > 0 {
+			b.WriteString("\n")
+		}
+		prefix := "-  "
+		if l.Ordered {
+			prefix = fmt.Sprintf("%d. ", i+1)
+		}
+		if item.Checked != nil {
+			check := " "
+			if *item.Checked {
+				check = "x"
+			}
+			prefix = fmt.Sprintf("- [%s] ", check)
+		}
+		b.WriteString(style.Dim.Render(prefix) + renderInline(item.Content))
+	}
+	return b.String()
+}
+
+func renderTable(t Table) string {
+	if len(t.Headers) == 0 {
+		return ""
+	}
+	var b strings.Builder
+
+	colWidths := make([]int, len(t.Headers))
+	for i, h := range t.Headers {
+		colWidths[i] = len(h)
+	}
+	for _, row := range t.Rows {
+		for i, cell := range row {
+			if i < len(colWidths) && len(cell) > colWidths[i] {
+				colWidths[i] = len(cell)
+			}
+		}
+	}
+
+	renderRow := func(cells []string, isHeader bool) {
+		b.WriteString("| ")
+		for i, cell := range cells {
+			if i > 0 {
+				b.WriteString(" | ")
+			}
+			if i < len(colWidths) {
+				cell = fmt.Sprintf("%-*s", colWidths[i], cell)
+			}
+			if isHeader {
+				b.WriteString(style.Bold.Render(cell))
+			} else {
+				b.WriteString(cell)
+			}
+		}
+		b.WriteString(" |")
+	}
+
+	renderRow(t.Headers, true)
+
+	sep := "| "
+	for i, w := range colWidths {
+		if i > 0 {
+			sep += " | "
+		}
+		sep += strings.Repeat("-", w)
+	}
+	sep += " |"
+	b.WriteString("\n" + style.Dim.Render(sep))
+
+	for _, row := range t.Rows {
+		b.WriteString("\n")
+		renderRow(row, false)
+	}
+
+	return b.String()
+}
+
+func renderBold(b Bold) string {
+	return style.New().Bold().Render(renderInline(b.Content))
+}
+
+func renderItalic(i Italic) string {
+	return style.New().Italic().Render(renderInline(i.Content))
+}
+
+func renderInlineCode(c Code) string {
+	return style.New().Fg(style.ColorYellow).Render("`" + c.Text + "`")
+}
+
+func renderLink(l Link) string {
+	text := renderInline(l.Content)
+	url := l.URL
+	if text == "" {
+		text = url
+		url = ""
+	}
+	styled := style.New().Underline().Fg(style.ColorBlue).Render(text)
+	if url != "" {
+		styled += style.Dim.Render(" (" + url + ")")
+	}
+	return styled
+}