fix: restore PDF pen capture and overhaul sticky/pens/pages

Reinstall PenCaptureBinding so stylus ink hits again; keep finger Listener translucent under pinch; page-anchor sticky with drag/resize; OneNote pen slots (brush+width+color); blank-note multi-page; default side button to hold-select-text.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/editor/canvas/pen_slide_screen.dart

@@ -19,6 +19,7 @@ import '../engine/brush.dart';
 import '../engine/shape_geometry.dart';
 import '../input/pen_config.dart';
 import '../input/pen_input_service.dart';
+import '../input/pen_slots.dart';
 import '../input/pressure_curve.dart' show kNaturalPressureGamma;
 import '../layout/viewport_fit.dart';
 import '../pdf/slide_export.dart';
@@ -58,29 +59,21 @@ class _PenSlideScreenState extends State<PenSlideScreen> {
   /// The single active-tool state (shared model across the 3 editors).
   EditorToolKind _tool = EditorToolKind.brush;
 
-  /// Selected brush for the BRUSH tool. Highlighter tool uses the highlighter
-  /// brush; local state only (not persisted — TODO(brush-persist-selection)).
-  BrushKind _penBrush = BrushKind.fountainPen;
-
   /// Selected shape for the SHAPE tool.
   ShapeKind _shapeKind = ShapeKind.line;
 
   /// Index of the currently selected committed stroke (SELECT tool), or null.
   int? _selectedStroke;
 
-  /// rnote-style per-brush color memory (see PenNoteScreen). In-memory only.
-  final Map<BrushKind, Color> _brushColors = {
-    BrushKind.fountainPen: Colors.black,
-    BrushKind.ballpoint: Colors.blue,
-    BrushKind.pencil: Colors.green,
-    BrushKind.highlighter: Colors.orange,
-  };
+  /// Highlighter keeps its own color (not a pen slot).
+  Color _highlighterColor = Colors.orange;
 
-  BrushKind get _activeColorBrush => _tool == EditorToolKind.highlighter
-      ? BrushKind.highlighter
-      : _penBrush;
+  BrushKind get _penBrush =>
+      _penSlots?.active.brush ?? BrushKind.fountainPen;
 
-  Color get _color => _brushColors[_activeColorBrush] ?? Colors.black;
+  Color get _color => _tool == EditorToolKind.highlighter
+      ? _highlighterColor
+      : (_penSlots?.active.color ?? Colors.black);
 
   bool _allowFingerDrawing = false;
   bool _needsCenter = true;
@@ -88,9 +81,9 @@ class _PenSlideScreenState extends State<PenSlideScreen> {
   double? _scrub;
 
   PenConfigController? _penConfig;
+  PenSlotsController? _penSlots;
   final TransformationController _transform = TransformationController();
 
-  static const double _penWidthFraction = 0.006;
   static const double _highlighterWidthFraction = 0.02;
   static const Size _fallbackSlide = Size(1600, 900);
 
@@ -125,15 +118,23 @@ class _PenSlideScreenState extends State<PenSlideScreen> {
   }
 
   Future<void> _initPenConfig() async {
-    final controller = await PenConfigController.load();
+    final results = await Future.wait([
+      PenConfigController.load(),
+      PenSlotsController.load(),
+    ]);
+    final config = results[0] as PenConfigController;
+    final slots = results[1] as PenSlotsController;
     if (!mounted) {
-      controller.dispose();
+      config.dispose();
+      slots.dispose();
       return;
     }
-    controller.addListener(_onPenConfigChanged);
+    config.addListener(_onPenConfigChanged);
+    slots.addListener(_onPenSlotsChanged);
     setState(() {
-      _penConfig = controller;
-      _allowFingerDrawing = controller.value.fingerDrawing;
+      _penConfig = config;
+      _penSlots = slots;
+      _allowFingerDrawing = config.value.fingerDrawing;
     });
   }
 
@@ -141,10 +142,16 @@ class _PenSlideScreenState extends State<PenSlideScreen> {
     if (mounted) setState(() {});
   }
 
+  void _onPenSlotsChanged() {
+    if (mounted) setState(() {});
+  }
+
   @override
   void dispose() {
     _penConfig?.removeListener(_onPenConfigChanged);
     _penConfig?.dispose();
+    _penSlots?.removeListener(_onPenSlotsChanged);
+    _penSlots?.dispose();
     _transform.dispose();
     super.dispose();
   }
@@ -300,7 +307,7 @@ class _PenSlideScreenState extends State<PenSlideScreen> {
 
   double get _strokeWidth => _tool == EditorToolKind.highlighter
       ? (_penConfig?.value.highlighterWidth ?? _highlighterWidthFraction)
-      : (_penConfig?.value.penWidth ?? _penWidthFraction);
+      : (_penSlots?.active.width ?? 0.006);
 
   // ── SELECT tool: select / move / delete (per-slide, reuses the undo stacks) ──
 
@@ -465,17 +472,19 @@ class _PenSlideScreenState extends State<PenSlideScreen> {
         child: Row(
           mainAxisSize: MainAxisSize.min,
           children: [
-            // OneNote-style: each pen is its own slot with remembered color.
-            for (final b in kPenToolBrushes)
+            // OneNote-style: each pen slot restores brush + color + thickness.
+            for (final slot in _penSlots?.slots ?? kDefaultPenSlots())
               PenSlotButton(
-                kind: b,
-                selected: _tool == EditorToolKind.brush && _penBrush == b,
-                color: _brushColors[b] ?? Colors.black,
-                tooltip: brushLabelEn(b),
-                onPressed: () => setState(() {
-                  _penBrush = b;
-                  _tool = EditorToolKind.brush;
-                }),
+                kind: slot.brush,
+                selected: _tool == EditorToolKind.brush &&
+                    (_penSlots?.activeId ?? 'slot_0') == slot.id,
+                color: slot.color,
+                widthHint: slot.width,
+                tooltip: brushLabelEn(slot.brush),
+                onPressed: () {
+                  _penSlots?.select(slot.id);
+                  setState(() => _tool = EditorToolKind.brush);
+                },
               ),
             ToolButton(
               icon: Icons.brush_outlined,
@@ -530,6 +539,10 @@ class _PenSlideScreenState extends State<PenSlideScreen> {
             ),
             PaletteDivider(cs: cs),
             for (final c in _palette) _colorDot(c, cs),
+            ThicknessPickerButton(
+              width: _penSlots?.active.width ?? 0.006,
+              onChanged: (w) => _penSlots?.setActiveWidth(w),
+            ),
             PaletteDivider(cs: cs),
             ToolButton(
               icon: _allowFingerDrawing ? Icons.touch_app : Icons.do_not_touch,
@@ -558,13 +571,17 @@ class _PenSlideScreenState extends State<PenSlideScreen> {
         _tool != EditorToolKind.eraser &&
         _tool != EditorToolKind.select;
     return GestureDetector(
-      onTap: () => setState(() {
+      onTap: () {
         if (_tool == EditorToolKind.eraser ||
             _tool == EditorToolKind.select) {
-          _tool = EditorToolKind.brush;
+          setState(() => _tool = EditorToolKind.brush);
         }
-        _brushColors[_activeColorBrush] = c;
-      }),
+        if (_tool == EditorToolKind.highlighter) {
+          setState(() => _highlighterColor = c);
+        } else {
+          _penSlots?.setActiveColor(c);
+        }
+      },
       child: AnimatedContainer(
         duration: const Duration(milliseconds: 150),
         margin: const EdgeInsets.symmetric(horizontal: 3),