Remove unnecessary 'from' check for copy command in shell

The shell copy command always uses current context as source, users never specify a separate 'from'.

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Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

Author: 3 people

src/Shell/CommandExecutor.php

@@ -105,8 +105,8 @@ protected function addContextIfNeeded(string $command, array &$input): void
             $input['--vault'] = $this->context->getVault();
         }
 
-        // Special handling for copy command's 'from' context
-        if ($command === 'copy' && !isset($input['--from'])) {
+        // Copy command always uses current context as 'from'
+        if ($command === 'copy') {
             $input['--from'] = sprintf(
                 "%s:%s",
                 $this->context->getVault(),