feat: add safe agent writeback flow

internal/agents/store.go

@@ -90,6 +90,7 @@ func (s Store) readOne(fileName string) AgentDefinition {
 		def.ParseError = err.Error()
 		return def
 	}
+	def.Content = string(data)
 	values, err := parseSimpleTOML(string(data))
 	if err != nil {
 		def.ParseStatus = "invalid"