fix: improve input keybindings, user message rendering, and scrollback ordering

- Change newline keybinding from alt+enter to shift+enter across all
  input components (main input, slash command input, prompt overlay)
- Skip markdown rendering for plain-text user messages so newlines are
  preserved without extra paragraph spacing from glamour
- Fix scrollback ordering: defer queued user message printing to
  SpinnerEvent where previous stream content is guaranteed complete,
  combining flush + user message into a single tea.Println call

internal/ui/compact_renderer.go

@@ -47,12 +47,17 @@ func (r *CompactRenderer) RenderUserMessage(content string, timestamp time.Time)
 	symbol := lipgloss.NewStyle().Foreground(theme.Secondary).Render(">")
 	label := lipgloss.NewStyle().Foreground(theme.Secondary).Bold(true).Render("User")
 
-	// Convert single newlines to paragraph breaks so they survive glamour's
-	// markdown rendering (glamour treats single \n as a soft break).
-	content = strings.ReplaceAll(content, "\n", "\n\n")
-
-	// Format content for user messages (preserve formatting, no truncation)
-	compactContent := r.formatUserAssistantContent(content)
+	// Only run markdown rendering when the message contains code spans or
+	// fenced code blocks. Plain text is rendered directly so that newlines
+	// are preserved without the extra paragraph spacing glamour adds.
+	var compactContent string
+	if strings.Contains(content, "`") {
+		mdContent := strings.ReplaceAll(content, "\n", "\n\n")
+		compactContent = r.formatUserAssistantContent(mdContent)
+		compactContent = removeBlankLines(compactContent)
+	} else {
+		compactContent = content
+	}
 
 	// Handle multi-line content
 	lines := strings.Split(compactContent, "\n")

internal/ui/input.go

@@ -89,10 +89,10 @@ func NewInputComponent(width int, title string, appCtrl AppController) *InputCom
 	ta.SetHeight(3)        // Default to 3 lines like huh
 	ta.Focus()
 
-	// Override InsertNewline so only ctrl+j and alt+enter insert newlines.
+	// Override InsertNewline so only ctrl+j and shift+enter insert newlines.
 	// Enter always submits the input.
 	ta.KeyMap.InsertNewline = key.NewBinding(
-		key.WithKeys("ctrl+j", "alt+enter"),
+		key.WithKeys("ctrl+j", "shift+enter"),
 		key.WithHelp("ctrl+j", "insert newline"),
 	)
 
@@ -419,7 +419,7 @@ func (s *InputComponent) View() tea.View {
 			MarginTop(1).
 			PaddingLeft(3)
 
-		hint := "enter submit • ctrl+j / alt+enter new line • ctrl+v paste image"
+		hint := "enter submit • ctrl+j / shift+enter new line • ctrl+v paste image"
 		view.WriteString("\n")
 		view.WriteString(helpStyle.Render(hint))
 	}

internal/ui/messages.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"os/user"
+	"regexp"
 	"sort"
 	"strings"
 	"time"
@@ -12,6 +13,9 @@ import (
 	"charm.land/lipgloss/v2"
 )
 
+// ansiEscapeRe matches ANSI escape sequences used for terminal styling.
+var ansiEscapeRe = regexp.MustCompile(`\x1b\[[0-9;]*m`)
+
 // MessageType represents different categories of messages displayed in the UI,
 // each with distinct visual styling and formatting rules.
 type MessageType int
@@ -193,13 +197,21 @@ func (r *MessageRenderer) RenderUserMessage(content string, timestamp time.Time)
 	timeStr := timestamp.Local().Format("15:04")
 	username := getSystemUsername()
 
-	// Convert single newlines to paragraph breaks so they survive glamour's
-	// markdown rendering (glamour treats single \n as a soft break).
-	content = strings.ReplaceAll(content, "\n", "\n\n")
-
 	theme := getTheme()
 
-	messageContent := r.renderMarkdown(content, r.width-8) // Account for padding and borders
+	// Only run markdown rendering when the message contains code spans or
+	// fenced code blocks. Plain text is rendered directly so that newlines
+	// are preserved without the extra paragraph spacing glamour adds.
+	var messageContent string
+	if strings.Contains(content, "`") {
+		// Glamour treats single \n as a soft break, so convert to paragraph
+		// breaks and collapse the resulting blank lines after rendering.
+		mdContent := strings.ReplaceAll(content, "\n", "\n\n")
+		messageContent = r.renderMarkdown(mdContent, r.width-8)
+		messageContent = removeBlankLines(messageContent)
+	} else {
+		messageContent = content
+	}
 
 	// Create info line
 	info := fmt.Sprintf(" %s (%s)", username, timeStr)
@@ -710,3 +722,19 @@ func (r *MessageRenderer) renderMarkdown(content string, width int) string {
 	rendered := toMarkdown(content, width)
 	return strings.TrimSuffix(rendered, "\n")
 }
+
+// removeBlankLines removes lines that are visually blank from rendered output.
+// Glamour wraps every character (including padding spaces) with ANSI color
+// codes, so we must strip escape sequences before checking whether a line is
+// empty. This collapses paragraph spacing so user messages render without
+// extra vertical gaps.
+func removeBlankLines(s string) string {
+	lines := strings.Split(s, "\n")
+	filtered := lines[:0]
+	for _, line := range lines {
+		if strings.TrimSpace(ansiEscapeRe.ReplaceAllString(line, "")) != "" {
+			filtered = append(filtered, line)
+		}
+	}
+	return strings.Join(filtered, "\n")
+}

internal/ui/model.go

@@ -396,6 +396,12 @@ type AppModel struct {
 	// the input and move to scrollback when the agent picks them up.
 	queuedMessages []string
 
+	// pendingUserPrints holds user messages that have been consumed from the
+	// queue but not yet printed to scrollback. They are deferred until
+	// SpinnerEvent{Show: true} so the previous assistant response can be
+	// flushed first, preserving chronological order.
+	pendingUserPrints []string
+
 	// canceling tracks whether the user has pressed ESC once during stateWorking.
 	// A second ESC within 2 seconds will cancel the current step.
 	canceling bool
@@ -1091,12 +1097,16 @@ func (m *AppModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			if qLen > 0 {
 				// Queued: anchor the message text above the input with a
 				// "queued" badge. It will be printed to scrollback when
-				// the agent picks it up (on QueueUpdatedEvent).
+				// the agent picks it up (via SpinnerEvent).
 				m.queuedMessages = append(m.queuedMessages, displayText)
 				m.distributeHeight()
 			} else {
-				// Started immediately: print to scrollback now.
-				cmds = append(cmds, m.printUserMessage(displayText))
+				// Started immediately. Flush any leftover stream content
+				// from the previous step first, then print the user
+				// message — combined in a single tea.Println so
+				// scrollback stays in chronological order.
+				m.pendingUserPrints = append(m.pendingUserPrints, displayText)
+				cmds = append(cmds, m.flushStreamAndPendingUserMessages())
 			}
 		} else {
 			cmds = append(cmds, m.printUserMessage(displayText))
@@ -1119,10 +1129,11 @@ func (m *AppModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		// SpinnerEvent{Show: true} means a new agent step has started (either
 		// freshly or from the queue after a previous step completed). Flush
 		// any leftover stream content from the previous step to scrollback
-		// before starting the new one. This deferred flush avoids shrinking
-		// the view at step-completion time (which leaves blank lines).
+		// before starting the new one, followed by any pending user messages
+		// from the queue. Everything is emitted in a single tea.Println to
+		// guarantee chronological ordering in scrollback.
 		if msg.Show {
-			cmds = append(cmds, m.flushStreamContent())
+			cmds = append(cmds, m.flushStreamAndPendingUserMessages())
 			m.state = stateWorking
 			m.distributeHeight()
 		}
@@ -1189,13 +1200,14 @@ func (m *AppModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		// Informational — no action needed by parent.
 
 	case app.QueueUpdatedEvent:
-		// drainQueue popped item(s) from the queue. Move consumed messages
-		// from the anchored display to scrollback (they are now being processed
-		// or about to be).
+		// drainQueue popped item(s) from the queue. Move consumed
+		// messages to pendingUserPrints — they will be printed to
+		// scrollback in the next SpinnerEvent{Show: true} after the
+		// previous assistant response is flushed.
 		for len(m.queuedMessages) > msg.Length {
 			text := m.queuedMessages[0]
 			m.queuedMessages = m.queuedMessages[1:]
-			cmds = append(cmds, m.printUserMessage(text))
+			m.pendingUserPrints = append(m.pendingUserPrints, text)
 		}
 		m.distributeHeight()
 
@@ -2080,8 +2092,7 @@ func (m *AppModel) printCompactResult(evt app.CompactCompleteEvent) tea.Cmd {
 // and on step completion.
 //
 // After flushing, a ClearScreen is issued to force a full terminal redraw.
-// When
-// the stream content is moved to scrollback the view height shrinks, and
+// When the stream content is moved to scrollback the view height shrinks, and
 // bubbletea's inline renderer doesn't clear the orphaned terminal rows
 // below the managed region. ClearScreen ensures a clean redraw.
 func (m *AppModel) flushStreamContent() tea.Cmd {
@@ -2099,6 +2110,37 @@ func (m *AppModel) flushStreamContent() tea.Cmd {
 	)
 }
 
+// flushStreamAndPendingUserMessages flushes the previous assistant response
+// and any pending queued user messages to scrollback in a single tea.Println
+// call, guaranteeing chronological order. Called from SpinnerEvent{Show: true}
+// where all previous stream chunks are guaranteed to have been processed.
+func (m *AppModel) flushStreamAndPendingUserMessages() tea.Cmd {
+	var parts []string
+
+	// 1. Flush previous stream content (assistant response).
+	if m.stream != nil {
+		if content := m.stream.GetRenderedContent(); content != "" {
+			m.stream.Reset()
+			parts = append(parts, content)
+		}
+	}
+
+	// 2. Render pending user messages from the queue.
+	for _, text := range m.pendingUserPrints {
+		rendered := m.renderer.RenderUserMessage(text, time.Now()).Content
+		parts = append(parts, rendered)
+	}
+	m.pendingUserPrints = nil
+
+	if len(parts) == 0 {
+		return nil
+	}
+	return tea.Sequence(
+		tea.Println(strings.Join(parts, "\n")),
+		func() tea.Msg { return tea.ClearScreen() },
+	)
+}
+
 // distributeHeight recalculates child component heights after a window resize,
 // queue change, widget update, or state transition, and propagates the computed
 // stream height to the StreamComponent.

internal/ui/model_test.go

@@ -405,14 +405,16 @@ func TestQueuedMessages_storedOnQueuedSubmit(t *testing.T) {
 }
 
 // TestQueuedMessages_poppedOnQueueUpdated verifies that QueueUpdatedEvent pops
-// consumed messages from queuedMessages and prints them to scrollback.
+// consumed messages from queuedMessages and moves them to pendingUserPrints.
+// The actual printing is deferred to SpinnerEvent{Show: true} to preserve
+// chronological order with the preceding assistant response.
 func TestQueuedMessages_poppedOnQueueUpdated(t *testing.T) {
 	ctrl := &stubAppController{}
 	m, _, _ := newTestAppModel(ctrl)
 	m.queuedMessages = []string{"first", "second", "third"}
 
 	// Simulate drainQueue popping one item (length goes from 3 to 2).
-	_, cmd := m.Update(app.QueueUpdatedEvent{Length: 2})
+	m = sendMsg(m, app.QueueUpdatedEvent{Length: 2})
 
 	if len(m.queuedMessages) != 2 {
 		t.Fatalf("expected 2 queued messages after pop, got %d", len(m.queuedMessages))
@@ -420,14 +422,17 @@ func TestQueuedMessages_poppedOnQueueUpdated(t *testing.T) {
 	if m.queuedMessages[0] != "second" {
 		t.Fatalf("expected first remaining message 'second', got %q", m.queuedMessages[0])
 	}
-	// Should produce a cmd (tea.Println for the popped user message).
-	if cmd == nil {
-		t.Fatal("expected non-nil cmd (tea.Println) for popped message")
+	// Popped message should be deferred to pendingUserPrints.
+	if len(m.pendingUserPrints) != 1 {
+		t.Fatalf("expected 1 pending user print, got %d", len(m.pendingUserPrints))
+	}
+	if m.pendingUserPrints[0] != "first" {
+		t.Fatalf("expected pending message 'first', got %q", m.pendingUserPrints[0])
 	}
 }
 
 // TestQueuedMessages_allPoppedOnDrain verifies that QueueUpdatedEvent with
-// Length=0 pops all remaining queued messages.
+// Length=0 pops all remaining queued messages into pendingUserPrints.
 func TestQueuedMessages_allPoppedOnDrain(t *testing.T) {
 	ctrl := &stubAppController{}
 	m, _, _ := newTestAppModel(ctrl)
@@ -438,6 +443,9 @@ func TestQueuedMessages_allPoppedOnDrain(t *testing.T) {
 	if len(m.queuedMessages) != 0 {
 		t.Fatalf("expected 0 queued messages after drain, got %d", len(m.queuedMessages))
 	}
+	if len(m.pendingUserPrints) != 2 {
+		t.Fatalf("expected 2 pending user prints, got %d", len(m.pendingUserPrints))
+	}
 }
 
 // --------------------------------------------------------------------------

internal/ui/prompt.go

@@ -83,7 +83,7 @@ func newInputPrompt(message, placeholder, defaultValue string, width, height int
 
 	// Prevent Enter from inserting a newline — we intercept it for submit.
 	ta.KeyMap.InsertNewline = key.NewBinding(
-		key.WithKeys("ctrl+j", "alt+enter"),
+		key.WithKeys("ctrl+j", "shift+enter"),
 	)
 
 	if defaultValue != "" {

internal/ui/slash_command_input.go

@@ -42,10 +42,10 @@ func NewSlashCommandInput(width int, title string) *SlashCommandInput {
 	ta.SetHeight(3)        // Default to 3 lines like huh
 	ta.Focus()
 
-	// Override InsertNewline so only ctrl+j and alt+enter insert newlines.
+	// Override InsertNewline so only ctrl+j and shift+enter insert newlines.
 	// Enter always submits the input.
 	ta.KeyMap.InsertNewline = key.NewBinding(
-		key.WithKeys("ctrl+j", "alt+enter"),
+		key.WithKeys("ctrl+j", "shift+enter"),
 		key.WithHelp("ctrl+j", "insert newline"),
 	)
 
@@ -227,7 +227,7 @@ func (s *SlashCommandInput) View() tea.View {
 			MarginTop(1).
 			PaddingLeft(3)
 
-		helpText := "enter submit • ctrl+j / alt+enter new line"
+		helpText := "enter submit • ctrl+j / shift+enter new line"
 
 		view.WriteString("\n")
 		view.WriteString(helpStyle.Render(helpText))