移除旧版 HTML 模板与兼容层，并完善私信、举报、媒体存储与 SEO。

Co-authored-by: Cursor <cursoragent@cursor.com>

service/seo.go

@@ -0,0 +1,121 @@
+package service
+
+import (
+	"net/url"
+	"regexp"
+	"strings"
+	"time"
+	"unicode/utf8"
+
+	"git.iioio.com/freefire/jiang13-forum/model"
+)
+
+var (
+	imgSrcRe = regexp.MustCompile(`(?i)<img[^>]+src=["']([^"']+)["']`)
+)
+
+// SitemapURL 站点地图条目
+type SitemapURL struct {
+	Loc        string
+	LastMod    time.Time
+	ChangeFreq string
+	Priority   string
+}
+
+// SitePublicBaseURL 公开站点根地址（无尾斜杠）
+// 优先 OIDC / 配置中的 RootURL，否则根据请求 Host 推断
+func (s *ForumSettingsService) SitePublicBaseURL(cfgRoot, requestOrigin string) string {
+	root := normalizeRootURL(s.getString(SettingOIDCRootURL, ""))
+	if root == "" {
+		root = normalizeRootURL(cfgRoot)
+	}
+	if root == "" {
+		root = normalizeRootURL(requestOrigin)
+	}
+	return strings.TrimRight(root, "/")
+}
+
+// AbsoluteURL 将相对路径拼成绝对 URL
+func AbsoluteURL(base, pathOrURL string) string {
+	pathOrURL = strings.TrimSpace(pathOrURL)
+	if pathOrURL == "" {
+		return ""
+	}
+	if strings.HasPrefix(pathOrURL, "http://") || strings.HasPrefix(pathOrURL, "https://") {
+		return pathOrURL
+	}
+	base = strings.TrimRight(base, "/")
+	if !strings.HasPrefix(pathOrURL, "/") {
+		pathOrURL = "/" + pathOrURL
+	}
+	return base + pathOrURL
+}
+
+// TruncateRunes 按 rune 截断并加省略号
+func TruncateRunes(s string, max int) string {
+	s = strings.TrimSpace(s)
+	if max <= 0 || s == "" {
+		return s
+	}
+	if utf8.RuneCountInString(s) <= max {
+		return s
+	}
+	runes := []rune(s)
+	if max < 2 {
+		return string(runes[:max])
+	}
+	return string(runes[:max-1]) + "…"
+}
+
+// ExcerptFromHTML 从 HTML 生成摘要（剥离标签）
+func ExcerptFromHTML(htmlContent string, maxRunes int) string {
+	plain := StripHTMLForSearch(htmlContent)
+	return TruncateRunes(plain, maxRunes)
+}
+
+// FirstImageURL 提取正文中第一张图片的 src
+func FirstImageURL(htmlContent string) string {
+	m := imgSrcRe.FindStringSubmatch(htmlContent)
+	if len(m) < 2 {
+		return ""
+	}
+	src := strings.TrimSpace(m[1])
+	// 忽略 data: 内联图
+	if strings.HasPrefix(src, "data:") {
+		return ""
+	}
+	return src
+}
+
+// DisplayName 用户展示名
+func DisplayName(u *model.User) string {
+	if u == nil {
+		return ""
+	}
+	if n := strings.TrimSpace(u.Nickname); n != "" {
+		return n
+	}
+	return strings.TrimSpace(u.Username)
+}
+
+// QueryBoardHome 板块首页相对路径
+func QueryBoardHome(boardID uint) string {
+	if boardID == 0 {
+		return "/"
+	}
+	return "/?board=" + url.QueryEscape(itoaUint(boardID))
+}
+
+func itoaUint(n uint) string {
+	if n == 0 {
+		return "0"
+	}
+	var buf [20]byte
+	i := len(buf)
+	for n > 0 {
+		i--
+		buf[i] = byte('0' + n%10)
+		n /= 10
+	}
+	return string(buf[i:])
+}