fix(ui): improve preview pane and JSONB viewer scrolling

- Fix JSONB viewer dimensions based on terminal size (max 100 chars wide)
- Change preview pane scroll keys from Ctrl+↑↓ to J/K for consistency
- Change JSONB viewer open key from J to v to free up J/K for scrolling
- Add J/K scroll support in JSONB viewer's preview pane
- Update help text to reflect new key bindings

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: rebelice

internal/app/app.go

@@ -1227,10 +1227,10 @@ func (a *App) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 				// Handle preview pane scrolling (when visible)
 				if activeTable != nil && activeTable.PreviewPane != nil && activeTable.PreviewPane.Visible {
 					switch msg.String() {
-					case "ctrl+up":
+					case "K":
 						activeTable.PreviewPane.ScrollUp()
 						return a, nil
-					case "ctrl+down":
+					case "J":
 						activeTable.PreviewPane.ScrollDown()
 						return a, nil
 					}
@@ -1419,12 +1419,19 @@ func (a *App) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 						}
 					}
 					return a, nil
-				case "J":
-					// Open JSONB viewer if cell contains JSONB (uppercase J to avoid conflict with vim down)
+				case "v":
+					// Open JSONB viewer if cell contains JSONB
 					selectedRow, selectedCol := activeTable.GetSelectedCell()
 					if selectedRow >= 0 && selectedCol >= 0 && selectedRow < len(activeTable.Rows) && selectedCol < len(activeTable.Columns) {
 						cellValue := activeTable.Rows[selectedRow][selectedCol]
 						if jsonb.IsJSONB(cellValue) {
+							// Set viewer dimensions based on terminal size (with max width limit)
+							viewerWidth := a.state.Width * 2 / 3
+							if viewerWidth > 100 {
+								viewerWidth = 100
+							}
+							a.jsonbViewer.Width = viewerWidth
+							a.jsonbViewer.Height = a.state.Height * 3 / 4
 							if err := a.jsonbViewer.SetValue(cellValue); err == nil {
 								a.showJSONBViewer = true
 							}
@@ -3007,6 +3014,13 @@ func (a *App) handleMouseEvent(msg tea.MouseMsg) (tea.Model, tea.Cmd) {
 								cellValue := activeTable.Rows[actualRow][actualCol]
 								// Check if it's JSON/JSONB data
 								if jsonb.IsJSONB(cellValue) {
+									// Set viewer dimensions based on terminal size (with max width limit)
+									viewerWidth := a.state.Width * 2 / 3
+									if viewerWidth > 100 {
+										viewerWidth = 100
+									}
+									a.jsonbViewer.Width = viewerWidth
+									a.jsonbViewer.Height = a.state.Height * 3 / 4
 									if err := a.jsonbViewer.SetValue(cellValue); err == nil {
 										a.showJSONBViewer = true
 									}

internal/ui/components/jsonb_viewer.go

@@ -444,14 +444,6 @@ func (jv *JSONBViewer) Update(msg tea.KeyMsg) (*JSONBViewer, tea.Cmd) {
 			jv.adjustScroll()
 		}
 
-	case "J":
-		// Jump to next sibling
-		jv.jumpToNextSibling()
-
-	case "K":
-		// Jump to previous sibling
-		jv.jumpToPrevSibling()
-
 	case "p":
 		// Toggle preview pane
 		if jv.previewPane != nil {
@@ -460,6 +452,22 @@ func (jv *JSONBViewer) Update(msg tea.KeyMsg) (*JSONBViewer, tea.Cmd) {
 			jv.previewPane.Toggle()
 		}
 
+	case "K":
+		// Scroll preview pane up (when visible), otherwise jump to previous sibling
+		if jv.previewPane != nil && jv.previewPane.Visible {
+			jv.previewPane.ScrollUp()
+		} else {
+			jv.jumpToPrevSibling()
+		}
+
+	case "J":
+		// Scroll preview pane down (when visible), otherwise jump to next sibling
+		if jv.previewPane != nil && jv.previewPane.Visible {
+			jv.previewPane.ScrollDown()
+		} else {
+			jv.jumpToNextSibling()
+		}
+
 	case "P":
 		// Jump to parent
 		jv.jumpToParent()
@@ -846,7 +854,7 @@ func (jv *JSONBViewer) RenderPreviewPanel(width, height int) string {
 	// Footer with help text
 	helpParts := []string{}
 	if jv.previewPane.IsScrollable() {
-		helpParts = append(helpParts, "Ctrl-↑↓: Scroll")
+		helpParts = append(helpParts, "J/K: Scroll")
 	}
 	helpParts = append(helpParts, "y: Copy", "p: Toggle")
 

internal/ui/components/preview_pane.go

@@ -260,13 +260,13 @@ func (p *PreviewPane) View() string {
 	// Build help text - use abbreviated form for narrow panes
 	helpParts := []string{}
 	if p.IsScrollable() {
-		helpParts = append(helpParts, "↑↓")
+		helpParts = append(helpParts, "J/K:scroll")
 	}
 	helpParts = append(helpParts, "y:copy", "p:close")
 
 	// Add JSONB hint if content is JSON
 	if jsonb.IsJSONB(p.Content) {
-		helpParts = append(helpParts, "J:tree")
+		helpParts = append(helpParts, "v:tree")
 	}
 
 	helpText := strings.Join(helpParts, " ")