Improve disk UI and build performance

internal/watcher/watcher.go

@@ -2,6 +2,7 @@ package watcher
 
 import (
 	"context"
+	"os"
 	"path/filepath"
 	"sort"
 	"sync"
@@ -121,22 +122,17 @@ func (w *Watcher) probe() {
 }
 
 func discoverDisks(root string) map[string]disk.DiskInfo {
-	candidates := []string{root}
-
-	if entries, err := filepath.Glob(filepath.Join(root, "*")); err == nil {
-		for _, path := range entries {
-			candidates = append(candidates, path)
-		}
+	entries, err := os.ReadDir(root)
+	if err != nil {
+		return map[string]disk.DiskInfo{}
 	}
 
 	disks := make(map[string]disk.DiskInfo)
-	seen := make(map[string]struct{}, len(candidates))
-	for _, mountPath := range candidates {
-		if _, ok := seen[mountPath]; ok {
+	for _, entry := range entries {
+		if !entry.IsDir() {
 			continue
 		}
-		seen[mountPath] = struct{}{}
-
+		mountPath := filepath.Join(root, entry.Name())
 		info, _ := disk.Probe(mountPath)
 		if info.State == disk.DiskAbsent {
 			continue