all: log and simplify error when source file is not exist

Previously, if the source file to be copied is not exist, awwan will
output only error for the ".vault" file, twice, for example

  !!! Copy: <source>.vault: open <source>.vault not exist
  Local: Copy: <source>.vault: open <source>.vault not exist

This changes make the first line output to print the original source
file first, the non-ecrypted one, and then followed by encrypted one,

  ??? loadFileInput "<source>": not exist
  Local: Copy "<source>.vault": not exist

1 files changed, 11 insertions, 5 deletions

diff --git a/session.go b/session.go
index 6df9215..c3da636 100644
--- a/session.go
+++ b/session.go
@@ -514,7 +514,6 @@ func (ses *Session) executeScriptOnRemote(req *Request, pos linePosition) (err e
 			err = ses.SudoPut(req, stmt)
 		}
 		if err != nil {
-			fmt.Fprintf(req.stderr, "!!! %s\n", err)
 			return err
 		}
 	}
@@ -699,27 +698,34 @@ func (ses *Session) loadFileEnv(awwanEnv string, isVault bool) (err error) {
 // On success, it will return the content of file and true if the file is
 // from encrypted file .vault.
 func (ses *Session) loadFileInput(path string) (content []byte, isVault bool, err error) {
-	var relPath = relativePath(ses.BaseDir, path)
+	var (
+		logp    = `loadFileInput`
+		relPath = relativePath(ses.BaseDir, path)
+	)
 
 	content, err = os.ReadFile(path)
 	if err == nil {
 		return content, false, nil
 	}
 	if !errors.Is(err, fs.ErrNotExist) {
-		return nil, false, fmt.Errorf(`%s: %s`, relPath, err)
+		return nil, false, err
 	}
+	log.Printf(`??? %s %q: not exist`, logp, relPath)
 
 	path = path + defEncryptExt
 	relPath += defEncryptExt
 
 	content, err = os.ReadFile(path)
 	if err != nil {
-		return nil, false, fmt.Errorf(`%s: %s`, relPath, err)
+		if errors.Is(err, fs.ErrNotExist) {
+			return nil, false, fmt.Errorf(`%s %q: %w`, logp, relPath, fs.ErrNotExist)
+		}
+		return nil, false, err
 	}
 
 	content, err = ses.cryptoc.decrypt(content)
 	if err != nil {
-		return nil, false, fmt.Errorf(`%s: %s`, relPath, err)
+		return nil, false, fmt.Errorf(`%s %q: %s`, logp, relPath, err)
 	}
 
 	return content, true, nil