重构: 连接切换链收敛与代码清理

- 切换连接统一switchConnection入口，删watcher与抑制机制
- 删除活跃服务器后回落本地并加载
- 侧边栏与指示器点击统一上抛，重复点击可刷新
- Wails事件解析归一，查重谓词抽公共
- 删空壳别名文件与过期文档截图

internal/filesystem/encoding.go

@@ -1,24 +0,0 @@
-package filesystem
-
-import (
-	"bytes"
-	"io"
-	"unicode/utf8"
-
-	"golang.org/x/text/encoding/simplifiedchinese"
-	"golang.org/x/text/transform"
-)
-
-// BytesToString 智能编码转换：UTF-8 直接返回，否则尝试 GBK → UTF-8
-func BytesToString(data []byte) string {
-	if utf8.Valid(data) {
-		return string(data)
-	}
-	// 尝试 GBK 解码
-	reader := transform.NewReader(bytes.NewReader(data), simplifiedchinese.GBK.NewDecoder())
-	decoded, err := io.ReadAll(reader)
-	if err != nil || !utf8.Valid(decoded) {
-		return string(data) // 转换失败或结果无效，返回原始内容
-	}
-	return string(decoded)
-}

internal/filesystem/site_resource.go

@@ -1,47 +0,0 @@
-package filesystem
-
-import (
-	"regexp"
-	"strings"
-)
-
-var (
-	htmlResRegex = regexp.MustCompile(`(?:src|href|data|poster)=["']([^"']+)["']`)
-	htmlCssUrlRe = regexp.MustCompile(`url\(\s*["']?([^"')]+)["']?\s*\)`)
-)
-
-// ExtractHtmlResources 从 HTML 内容提取资源路径
-func ExtractHtmlResources(html string) []string {
-	seen := make(map[string]bool)
-	var resources []string
-	add := func(v string) {
-		v = strings.TrimSpace(v)
-		if v != "" && !seen[v] {
-			seen[v] = true
-			resources = append(resources, v)
-		}
-	}
-	for _, m := range htmlResRegex.FindAllStringSubmatch(html, -1) {
-		if len(m) > 1 {
-			add(m[1])
-		}
-	}
-	for _, m := range htmlCssUrlRe.FindAllStringSubmatch(html, -1) {
-		if len(m) > 1 {
-			add(m[1])
-		}
-	}
-	return resources
-}
-
-// ShouldSkipResource 判断资源路径是否应跳过
-func ShouldSkipResource(p string) bool {
-	return strings.HasPrefix(p, "data:") ||
-		strings.HasPrefix(p, "http://") ||
-		strings.HasPrefix(p, "https://") ||
-		strings.HasPrefix(p, "//") ||
-		strings.HasPrefix(p, "#") ||
-		strings.HasPrefix(p, "javascript:") ||
-		strings.HasPrefix(p, "mailto:") ||
-		strings.HasPrefix(p, "blob:")
-}