fix: improve Claude Code ENOENT error handling with installation guidance

src/i18n/locales/en/common.json

@@ -83,7 +83,8 @@
 			"errorOutput": "Error output: {{output}}",
 			"processExitedWithError": "Claude Code process exited with code {{exitCode}}. Error output: {{output}}",
 			"stoppedWithReason": "Claude Code stopped with reason: {{reason}}",
-			"apiKeyModelPlanMismatch": "API keys and subscription plans allow different models. Make sure the selected model is included in your plan."
+			"apiKeyModelPlanMismatch": "API keys and subscription plans allow different models. Make sure the selected model is included in your plan.",
+			"notFound": "Claude Code executable '{{claudePath}}' not found.\n\nPlease install Claude Code CLI:\n1. Visit {{installationUrl}} to download Claude Code\n2. Follow the installation instructions for your operating system\n3. Ensure the 'claude' command is available in your PATH\n4. Alternatively, configure a custom path in Roo settings under 'Claude Code Path'\n\nOriginal error: {{originalError}}"
 		},
 		"gemini": {
 			"generate_stream": "Gemini generate context stream error: {{error}}",