refactor fstree to separate package

fs.go

@@ -1,123 +0,0 @@
-/*
-This file has the raw file io operations that are used by FsTree
-or elsewhere in the app. Nowhere else should there be a direct
-fileopen
-
-- ruinivist, 30Dec25
-*/
-
-package main
-
-import (
-	"errors"
-	"os"
-	"path/filepath"
-)
-
-func walkFileSystemAndBuildTree(rootPath string, node *FsNode) error {
-	if node == nil {
-		return errors.New("node cannot be nil")
-	}
-	if len(node.children) > 0 {
-		return errors.New("node already has children")
-	}
-
-	entries, err := os.ReadDir(rootPath)
-	if err != nil {
-		return err
-	}
-
-	for _, entry := range entries {
-		childPath := filepath.Join(rootPath, entry.Name())
-
-		var nodeType FsNodeType
-		if entry.IsDir() {
-			nodeType = FolderNode
-		} else {
-			nodeType = FileNode
-		}
-
-		childNode := &FsNode{
-			nodeType: nodeType,
-			path:     childPath,
-			children: make([]*FsNode, 0),
-			parent:   node,
-			expanded: false,
-		}
-
-		node.children = append(node.children, childNode)
-
-		// Recursively walk subdirectories
-		if entry.IsDir() {
-			if err := walkFileSystemAndBuildTree(childPath, childNode); err != nil {
-				return err
-			}
-		}
-	}
-
-	return nil
-}
-
-func createFile(path string, content []byte) error {
-	if path == "" {
-		return errors.New("file path cannot be empty")
-	}
-
-	if _, err := os.Stat(path); err == nil {
-		return errors.New("file already exists")
-	}
-
-	return os.WriteFile(path, content, 0644)
-}
-
-func createFolder(path string) error {
-	if path == "" {
-		return errors.New("folder path cannot be empty")
-	}
-
-	if _, err := os.Stat(path); err == nil {
-		return errors.New("folder already exists")
-	}
-
-	return os.Mkdir(path, 0755)
-}
-
-func deleteFile(path string) error {
-	if path == "" {
-		return errors.New("file path cannot be empty")
-	}
-
-	info, err := os.Stat(path)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return errors.New("file does not exist")
-		}
-		return err
-	}
-
-	if info.IsDir() {
-		return errors.New("path is a directory, not a file")
-	}
-
-	return os.Remove(path)
-}
-
-func deleteFolder(path string) error {
-	if path == "" {
-		return errors.New("folder path cannot be empty")
-	}
-
-	info, err := os.Stat(path)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return errors.New("folder does not exist")
-		}
-		return err
-	}
-
-	if !info.IsDir() {
-		return errors.New("path is a file, not a directory")
-	}
-
-	return os.RemoveAll(path)
-}