fix: trash file preview, visual CSS, virtual folder model

- Added resolveTrashPath() backend function: walks ancestor chain to find
  files inside deleted/moved folders (flat trash directory)
- Added TrashFsPath to TrashNodeDTO, computed during ListTrash via
  parent-to-child propagation of physical trash path
- Fixed visual CSS for trash rows: button reset (no white bg, transparent,
  inherit font/color), hover styles match app dark theme
- Root view filters out descendant nodes (only shows top-level items)

cmd/verstak-gui/bindings_trash.go

@@ -8,6 +8,8 @@ import (
 	"path/filepath"
 	"strings"
 	"time"
+
+	"verstak/internal/core/nodes"
 )
 
 type TrashDTO struct {
@@ -24,6 +26,7 @@ type TrashNodeDTO struct {
 	Type        string `json:"type"`
 	FsPath      string `json:"fsPath"`
 	NodePath    string `json:"nodePath"`
+	TrashFsPath string `json:"trashFsPath"`
 	DeletedAt   string `json:"deletedAt"`
 }
 
@@ -45,8 +48,13 @@ func (a *App) ListTrash() (*TrashDTO, error) {
 	if err != nil {
 		return nil, err
 	}
-	nodes := make([]TrashNodeDTO, 0, len(deleted))
+	// Phase 1: build all DTOs and compute direct trash paths for folder-type nodes.
+	nodeMap := make(map[string]*TrashNodeDTO, len(deleted))
+	var allDeleted []nodes.Node
 	for _, n := range deleted {
+		allDeleted = append(allDeleted, n)
+	}
+	for _, n := range allDeleted {
 		deletedAt := ""
 		if n.DeletedAt != nil {
 			deletedAt = n.DeletedAt.Format(time.RFC3339)
@@ -55,7 +63,7 @@ func (a *App) ListTrash() (*TrashDTO, error) {
 		if n.ParentID != nil {
 			parentID = *n.ParentID
 		}
-		nodes = append(nodes, TrashNodeDTO{
+		dto := &TrashNodeDTO{
 			ID:        n.ID,
 			ParentID:  parentID,
 			Title:     n.Title,
@@ -63,7 +71,49 @@ func (a *App) ListTrash() (*TrashDTO, error) {
 			FsPath:    n.FsPath,
 			NodePath:  a.nodes.Path(n.ID),
 			DeletedAt: deletedAt,
-		})
+		}
+		nodeMap[n.ID] = dto
+		// Try direct trash entry (for folders that were os.Rename'd).
+		if p, err := a.findTrashEntryForNode(n.ID); err == nil {
+			dto.TrashFsPath = p
+		}
+	}
+	// Phase 2: propagate trash paths from parents to children that have no direct entry
+	// but whose FsPath starts with the parent's FsPath.
+	changed := true
+	for changed {
+		changed = false
+		for _, n := range allDeleted {
+			dto := nodeMap[n.ID]
+			if dto.TrashFsPath != "" {
+				continue
+			}
+			parentID := ""
+			if n.ParentID != nil {
+				parentID = *n.ParentID
+			}
+			if parentID == "" {
+				continue
+			}
+			parent := nodeMap[parentID]
+			if parent == nil || parent.TrashFsPath == "" {
+				continue
+			}
+			// Child inherits parent's trash path + relative FsPath fragment.
+			if n.FsPath != "" && parent.FsPath != "" && strings.HasPrefix(n.FsPath, parent.FsPath) {
+				rel := strings.TrimPrefix(n.FsPath, parent.FsPath)
+				rel = strings.TrimPrefix(rel, "/")
+				if rel != "" {
+					dto.TrashFsPath = filepath.Join(parent.TrashFsPath, rel)
+					changed = true
+				}
+			}
+		}
+	}
+
+	nodes := make([]TrashNodeDTO, 0, len(deleted))
+	for _, dto := range nodeMap {
+		nodes = append(nodes, *dto)
 	}
 
 	entries, err := listTrashEntries(trashPath)
@@ -302,7 +352,7 @@ func (a *App) ReadTrashFileContent(nodeID string) (string, error) {
 	if err := a.requireVault(); err != nil {
 		return "", err
 	}
-	path, err := a.findTrashEntryForNode(nodeID)
+	path, err := a.resolveTrashPath(nodeID)
 	if err != nil {
 		return "", err
 	}
@@ -313,6 +363,91 @@ func (a *App) ReadTrashFileContent(nodeID string) (string, error) {
 	return string(data), nil
 }
 
+// resolveTrashPath finds the physical path of a deleted node's file in the trash.
+// For directly-moved entries (folders), it looks up <nodeID>_* in trash dir.
+// For nested files (moved as part of a parent folder), it walks up the ancestor
+// chain until it finds a folder with a direct trash entry, then appends the
+// relative filesystem path.
+func (a *App) resolveTrashPath(nodeID string) (string, error) {
+	// 1. Try direct lookup first (for nodes that were individually moved).
+	if p, err := a.findTrashEntryForNode(nodeID); err == nil {
+		return p, nil
+	}
+	// 2. Walk parent chain to find nearest ancestor with a direct trash entry.
+	type step struct {
+		ID     string
+		FsPath string
+		Title  string
+	}
+	var chain []step
+	current := nodeID
+	for current != "" {
+		n, err := a.nodes.Get(current)
+		if err != nil {
+			break
+		}
+		chain = append(chain, step{ID: n.ID, FsPath: n.FsPath, Title: n.Title})
+		if n.ParentID != nil {
+			current = *n.ParentID
+		} else {
+			current = ""
+		}
+	}
+	// chain[0] = the node itself, chain[len-1] = topmost ancestor.
+	// Walk from closest ancestor outward to find a trash entry.
+	for i := 0; i < len(chain); i++ {
+		anc := chain[i]
+		ancPath, err := a.findTrashEntryForNode(anc.ID)
+		if err != nil {
+			continue
+		}
+		// Build the relative path from this ancestor down to the original node.
+		// The node at index 0 is the target; any step between anc and index 0
+		// contributes a subdirectory name.
+		// We walk from anc up to target (index 0), collecting FsPath segments.
+		var relSegments []string
+		for j := 0; j < i; j++ {
+			child := chain[j]
+			if child.FsPath != "" && anc.FsPath != "" && strings.HasPrefix(child.FsPath, anc.FsPath) {
+				rel := strings.TrimPrefix(child.FsPath, anc.FsPath)
+				rel = strings.TrimPrefix(rel, "/")
+				if rel != "" {
+					relSegments = append(relSegments, rel)
+				} else if child.Title != "" {
+					relSegments = append(relSegments, child.Title)
+				}
+			} else if child.Title != "" {
+				relSegments = append(relSegments, child.Title)
+			}
+			anc = child
+		}
+		fullPath := ancPath
+		if len(relSegments) > 0 {
+			fullPath = filepath.Join(ancPath, filepath.Join(relSegments...))
+		}
+		if info, err := os.Stat(fullPath); err == nil && !info.IsDir() {
+			return fullPath, nil
+		}
+	}
+	// 3. Fallback: try node title as filename inside each ancestor's trash dir.
+	for _, anc := range chain {
+		ancPath, err := a.findTrashEntryForNode(anc.ID)
+		if err != nil {
+			continue
+		}
+		fi, err := os.Stat(ancPath)
+		if err != nil || !fi.IsDir() {
+			continue
+		}
+		// Try the node's title as a direct child file inside the ancestor dir.
+		candidate := filepath.Join(ancPath, chain[0].Title)
+		if info, err := os.Stat(candidate); err == nil && !info.IsDir() {
+			return candidate, nil
+		}
+	}
+	return "", fmt.Errorf("trash file not found for node %s", nodeID)
+}
+
 func (a *App) OpenTrashFolder() error {
 	if err := a.requireVault(); err != nil {
 		return err

cmd/verstak-gui/frontend-dist/index.html

@@ -19,8 +19,8 @@
       background: #13131f;
     }
   </style>
-  <script type="module" crossorigin src="/assets/main-PQ2CZjSe.js"></script>
-  <link rel="stylesheet" crossorigin href="/assets/main-Bomne4X7.css">
+  <script type="module" crossorigin src="/assets/main-DGUrUZ5X.js"></script>
+  <link rel="stylesheet" crossorigin href="/assets/main-BW6W9uAx.css">
 </head>
 <body>
   <div id="app"></div>

frontend/src/App.svelte

@@ -3870,13 +3870,15 @@
 .trash-section-head { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; min-height: 36px; }
 .trash-section-head h3 { margin: 0 0 2px; }
 .trash-section-head p { margin: 0; color: #8888a0; font-size: 12px; }
-.trash-row { display: grid; grid-template-columns: auto auto minmax(0, 1fr) auto; align-items: center; gap: 10px; padding: 9px 10px; border: 1px solid #2a2a3c; border-radius: 8px; background: #1a1a28; margin-bottom: 8px; cursor: default; }
+.trash-row { display: grid; grid-template-columns: auto auto minmax(0, 1fr) auto; align-items: center; gap: 10px; padding: 9px 10px; border: 1px solid #2a2a3c; border-radius: 8px; background: #1a1a28; margin-bottom: 8px; }
 .trash-row.folder { background: #1b2132; border-color: #303856; }
 .trash-row.selected { border-color: #6366f1; background: #20203a; }
-.trash-row-icon { color: #a5b4fc; display: inline-flex; align-items: center; justify-content: center; cursor: pointer; padding: 4px; border-radius: 4px; }
+.trash-row-icon { color: #a5b4fc; display: inline-flex; align-items: center; justify-content: center; cursor: pointer; padding: 4px; border-radius: 4px; background: transparent; border: none; }
 .trash-row-icon:hover { background: #222238; color: #e4e4ef; }
-.trash-row-main { display: flex; flex-direction: column; gap: 2px; min-width: 0; cursor: pointer; padding: 2px 0; }
+.trash-row-main { display: flex; flex-direction: column; gap: 2px; min-width: 0; padding: 2px 0; cursor: pointer; background: transparent; border: none; color: inherit; font: inherit; text-align: left; width: 100%; border-radius: 4px; }
+.trash-row-main:hover { background: rgba(255,255,255,0.03); }
 .trash-row-main:hover .trash-row-title { color: #a5b4fc; }
+.trash-row-main:focus-visible { outline: 2px solid #6366f1; outline-offset: 2px; }
 .trash-row-title { min-width: 0; color: #e4e4ef; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
 .trash-row-meta { color: #8ea0d8; font-size: 11px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
 .trash-row-date { color: #666; font-size: 11px; }