Switch remote deploy to vendored source builds

Move remote deployment to a vendored source bundle built on the target host via Docker so redeploys no longer require local cross-compilation or host Go installation.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

vendor/github.com/wailsapp/wails/v2/pkg/assetserver/fs.go

@@ -0,0 +1,75 @@
+package assetserver
+
+import (
+	"embed"
+	"fmt"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// FindEmbedRootPath finds the root path in the embed FS. It's the directory which contains all the files.
+func FindEmbedRootPath(fsys embed.FS) (string, error) {
+	stopErr := fmt.Errorf("files or multiple dirs found")
+
+	fPath := ""
+	err := fs.WalkDir(fsys, ".", func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+
+		if d.IsDir() {
+			fPath = path
+			if entries, dErr := fs.ReadDir(fsys, path); dErr != nil {
+				return dErr
+			} else if len(entries) <= 1 {
+				return nil
+			}
+		}
+
+		return stopErr
+	})
+
+	if err != nil && err != stopErr {
+		return "", err
+	}
+
+	return fPath, nil
+}
+
+func FindPathToFile(fsys fs.FS, file string) (string, error) {
+	stat, _ := fs.Stat(fsys, file)
+	if stat != nil {
+		return ".", nil
+	}
+	var indexFiles []string
+	err := fs.WalkDir(fsys, ".", func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if strings.HasSuffix(path, file) {
+			indexFiles = append(indexFiles, path)
+		}
+		return nil
+	})
+	if err != nil {
+		return "", err
+	}
+
+	if len(indexFiles) > 1 {
+		selected := indexFiles[0]
+		for _, f := range indexFiles {
+			if len(f) < len(selected) {
+				selected = f
+			}
+		}
+		path, _ := filepath.Split(selected)
+		return path, nil
+	}
+	if len(indexFiles) > 0 {
+		path, _ := filepath.Split(indexFiles[0])
+		return path, nil
+	}
+	return "", fmt.Errorf("%s: %w", file, os.ErrNotExist)
+}