Update system prompt handling (again)

Add `api.ApplySystemPrompt`, renamed `GetSystemPrompt` to
`DefaultSystemPrompt`.

pkg/cmd/new.go

@@ -25,20 +25,10 @@ func NewCmd(ctx *lmcli.Context) *cobra.Command {
 				return fmt.Errorf("No message was provided.")
 			}
 
-			var messages []api.Message
-
-			system := ctx.Config.GetSystemPrompt()
-			if system != "" {
-				messages = append(messages, api.Message{
-					Role:    api.MessageRoleSystem,
-					Content: system,
-				})
-			}
-
-			messages = append(messages, api.Message{
+			messages := []api.Message{{
 				Role:    api.MessageRoleUser,
 				Content: input,
-			})
+			}}
 
 			conversation, messages, err := ctx.Store.StartConversation(messages...)
 			if err != nil {

pkg/cmd/prompt.go

@@ -25,20 +25,10 @@ func PromptCmd(ctx *lmcli.Context) *cobra.Command {
 				return fmt.Errorf("No message was provided.")
 			}
 
-			var messages []api.Message
-
-			system := ctx.Config.GetSystemPrompt()
-			if system != "" {
-				messages = append(messages, api.Message{
-					Role:    api.MessageRoleSystem,
-					Content: system,
-				})
-			}
-
-			messages = append(messages, api.Message{
+			messages := []api.Message{{
 				Role:    api.MessageRoleUser,
 				Content: input,
-			})
+			}}
 
 			_, err = cmdutil.Prompt(ctx, messages, nil)
 			if err != nil {

pkg/cmd/util/util.go

@@ -22,11 +22,15 @@ func Prompt(ctx *lmcli.Context, messages []api.Message, callback func(api.Messag
 		return nil, err
 	}
 
-	requestParams := api.RequestParameters{
+	params := api.RequestParameters{
 		Model:       m,
 		MaxTokens:   *ctx.Config.Defaults.MaxTokens,
 		Temperature: *ctx.Config.Defaults.Temperature,
-		ToolBag:     ctx.EnabledTools,
+	}
+
+	system := ctx.DefaultSystemPrompt()
+	if system != "" {
+		messages = api.ApplySystemPrompt(messages, system, false)
 	}
 
 	content := make(chan api.Chunk)
@@ -36,7 +40,7 @@ func Prompt(ctx *lmcli.Context, messages []api.Message, callback func(api.Messag
 	go ShowDelayedContent(content)
 
 	reply, err := provider.CreateChatCompletionStream(
-		context.Background(), requestParams, messages, content,
+		context.Background(), params, messages, content,
 	)
 
 	if reply.Content != "" {