ui: the events list is a slide-over page; the left pane, its divider and the header toggle are gone

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/ui_app.hpp

@@ -789,26 +789,18 @@ struct App {
   /// `event_recording` is the trigger panel's switch and defaults on -- the cache is only useful if
   /// it was already on when the event you wanted happened.
   std::unique_ptr<EventStore> event_store;
-  /// Whether the cache holds anything, refreshed once a second: what keeps the history button on the bar
-  /// for a source whose events are already written, even with recording switched off.
+  /// Whether the cache holds anything, refreshed once a second: what keeps the dock's Events block and the
+  /// `events` page live for a source whose events are already written, even with recording switched off.
   bool events_cached = false;
   bool event_recording = false;
-  /// The events pane: its list, the revealer that holds it, the recording switch (in the trigger
-  /// panel, where the trigger's options live), and `events_thumb` -- the picture of the newest
+  /// The `events` page of the slide-over: its content box, its list, the recording switch (in the
+  /// trigger panel, where the trigger's options live), and `events_thumb` -- the picture of the newest
   /// event. Every row carries the picture of *its* event; this is the first one's, which is the one
-  /// the probe measures and which the pane does not put anywhere special.
-  GtkWidget* events_revealer = nullptr;
+  /// the probe measures and which the page does not put anywhere special.
+  GtkWidget* events_box = nullptr;
   GtkWidget* events_list = nullptr;
   GtkWidget* events_thumb = nullptr;
   GtkWidget* events_record_switch = nullptr;
-  /// The toolbar's event-history toggle: the pane is opened *on demand* from here (the item's own
-  /// arrangement), and the toggle only exists while trigger mode does -- there are no events without
-  /// a trigger, and a button that can never have anything to show is a button spent on nothing.
-  GtkWidget* events_toggle = nullptr;
-  /// The paned that holds the events pane and the plot, and the width the divider was last dragged
-  /// to. 240 by default: enough for the preview and the numbers beside it, and not a plot's worth.
-  GtkWidget* events_divider = nullptr;
-  int events_pane_width = 240;
   /// The Events block of the dock: the box, its list (compact rows, one per `EventRecord`, the record
   /// attached to each row as `udpscope-event`) and the Manage button.
   GtkWidget* dock_events_box = nullptr;
@@ -1228,6 +1220,9 @@ struct App {
   /// it keeps for a second latch (it is counting retries, not time).
   int dbg_events_step = 0;
   int dbg_events_wait = 0;
+  /// The plot area's allocated width before the first event was latched (the events probe), compared with
+  /// its width after: the events list is a slide-over page and no longer a column beside the plot.
+  int dbg_events_plot_w = 0;
   /// The event row the probe selected before it activated one, and how many rows were selected.
   /// Both are read back *after* the activation: a row pointer that is no longer the list's row 0,
   /// or a smaller count, says the activation rebuilt the list and so threw away the user's scroll
@@ -1753,8 +1748,6 @@ void on_pause_toggled(GtkToggleButton* button, gpointer user);
 void search_jump(App& app, double t);
 void update_search_panel(App& app);
 void sync_events_availability(App& app);
-/// Restates the events pane's divider position once a frame; see the definition.
-void sync_events_divider(App& app);
 /// The preferences dialog: one window, opened from the overflow menu. `apply_theme()` is separate
 /// because the theme is the one preference that takes effect without a restart.
 void open_preferences(App& app);