source: capability panels as side-stack pages, with a probe for the path

src/ui_app.hpp

@@ -109,6 +109,14 @@ struct TourView {
   void* done_user = nullptr;
 };
 
+/// One capability panel a source kind contributed to the side stack. `content` is the kind's own widget
+/// (made insensitive while the source is disconnected); the page wrapping it is named `name`.
+struct SourcePanelPage {
+  std::string name;   ///< stack page name: "source-" + the kind's panel id
+  std::string title;  ///< the pill's tooltip and accessible name; the page's own title stays empty
+  GtkWidget* content = nullptr;
+};
+
 struct App {
   ScopeModel* model = nullptr;
   Acquisition* acq = nullptr;
@@ -843,6 +851,9 @@ struct App {
   std::string source_kind = "udps";
   SourceConfig source_opts;
   std::string source_title;
+  /// The panels the source kind added to `side_stack`, in tab order. Empty for UDPS and in file mode.
+  std::vector<SourcePanelPage> source_panels;
+  bool source_has_datagrams = true;  ///< the kind reports raw datagrams; false leaves the capture button disabled
   guint layout_save_source = 0;
   bool layout_loaded = false;
   unsigned signal_generation = ~0u;
@@ -1558,6 +1569,14 @@ void on_config_save_as(GtkButton*, gpointer user);
 void config_dialog_refresh(ConfigDialog& d);
 void open_configurations(App& app);
 void save_layout_now(App& app);
+
+/// Capability panels (`src/ui_source.cpp`). `build_source_panels` adds the source kind's panels as
+/// pages of `side_stack`, once, before the first tick. `apply_source_panels` sets every panel's
+/// sensitivity from `connected` -- disabled, never hidden: the tab switcher owns visibility.
+/// `sync_source_panels` is the per-tick call: it applies the model's own connection flag.
+void build_source_panels(App& app);
+void apply_source_panels(App& app, bool connected);
+void sync_source_panels(App& app);
 bool save_configuration_as(App& app, const std::string& name, const std::string& comment);
 gboolean layout_save_tick(gpointer user);
 void schedule_layout_save(App& app);
@@ -1855,6 +1874,8 @@ gboolean stats_probe_report(gpointer user);
 gboolean stats_probe(gpointer user);
 gboolean side_tab_probe_report(gpointer user);
 gboolean side_tab_probe(gpointer user);
+gboolean source_kinds_probe_report(gpointer user);
+gboolean source_kinds_probe(gpointer user);
 gboolean pan_probe(gpointer user);
 gboolean arm_probe(gpointer user);
 gboolean trigrenum_probe_step3(gpointer user);