Read the text content of a file on the instance.
curl -X GET "https://api.chowder.dev/v1/instances/ins_abc123/files/content?path=openclaw.json" \ -H "Authorization: Bearer YOUR_API_KEY"
{ "path": "openclaw.json", "content": "{\n \"channels\": {\n \"discord\": {\n \"enabled\": true\n }\n }\n}" }