Update command flag handling

`lmcli chat` now supports common prompt flags (model, length, system
prompt, etc)

pkg/cmd/continue.go

@@ -44,7 +44,7 @@ func ContinueCmd(ctx *lmcli.Context) *cobra.Command {
 			fmt.Print(lastMessage.Content)
 
 			// Submit the LLM request, allowing it to continue the last message
-			continuedOutput, err := cmdutil.FetchAndShowCompletion(ctx, messages, nil)
+			continuedOutput, err := cmdutil.Prompt(ctx, messages, nil)
 			if err != nil {
 				return fmt.Errorf("error fetching LLM response: %v", err)
 			}
@@ -68,5 +68,6 @@ func ContinueCmd(ctx *lmcli.Context) *cobra.Command {
 			return ctx.Store.ConversationShortNameCompletions(toComplete), compMode
 		},
 	}
+	applyPromptFlags(ctx, cmd)
 	return cmd
 }