Add a wiring list dialog and an excluded-conductor count

Slice 4 of discussion #503, on top of slice 3 (#629): the smallest
surface that makes wiring_list_view visible, plus the diagnostic the
view needs to be honest about what it is missing.

Projet > "Liste de câblage (base de données)" opens a read-only table of
wiring_list_view, headed by a line stating how many conductors are
listed and, when non-zero, how many were excluded and why.

Deliberately not another exporter. QET already ships a wiring-list CSV
export (Projet > Exporter le plan de câblage, and --export-cables) which
walks the project XML; measured on the same projects it produces a row
per conductor and resolves labels correctly when the project has them.
Adding a second, competing CSV would be worse, not better -- the
database path's value is what it unlocks (terminal plans, BOM joins),
not replacing that export.

projectDataBase::excludedConductorCount() counts, from the live scene,
the conductors deliberately absent from the conductor table because a
terminal has no uuid. Counted from the scene precisely because the
database is where those conductors are not. Verified: 671 on
examples/industrial.qet (which has 1794 terminals and no terminal uuids
at all, so its list is empty and now says so), 0 on a project whose
elements do carry terminal uuids.

KNOWN GAP, not fixed here and the reason this is opened for discussion
rather than merge: after a save/reload the component columns are blank
for slave elements. populateElementTable()/populateElementInfoTable()
only insert Simple|Terminal|Master|Thumbnail, so slave elements -- relay
contacts, i.e. a large share of real wire endpoints -- have no row in
element_info for the view to read a label from. Measured on a two-slave-
contact project after reload: element rows 0, element_info rows 0,
terminal rows 2, conductor rows 1; the wire is listed (slice 3's LEFT
JOIN keeps it) but both component names are empty, where the existing
CSV export shows K1 -> K2 for the same file.

Closing that gap means widening a filter shared with the nomenclature
and summary views, which would change what those existing, shipped
features contain. That is a maintainer decision, not one to take
unilaterally inside an additive slice.

sources/qetdiagrameditor.cpp

@@ -53,6 +53,7 @@
 #include "ui/diagrameditorhandlersizewidget.h"
 #include "TerminalStrip/ui/addterminalstripitemdialog.h"
 #include "wiringlistexport.h"
+#include "ui/wiringlistdialog.h"
 #include "ui/terminalnumberingdialog.h"
 #include <QDateTime>
 #include <QDebug>
@@ -503,6 +504,17 @@ void QETDiagramEditor::setUpActions()
 		}
 	});
 
+	// Show the wiring list read from the project database
+	m_project_wiring_list_view = new QAction(QET::Icons::DocumentSpreadsheet, tr("Liste de câblage (base de données)"), this);
+	connect(m_project_wiring_list_view, &QAction::triggered, [this]() {
+		QETProject *project = this->currentProject();
+		if (project)
+		{
+			WiringListDialog dialog(project, this);
+			dialog.exec();
+		}
+	});
+
 	// Terminal Numbering
 	m_terminal_numbering = new QAction(QET::Icons::TerminalStrip, tr("Numérotation automatique des bornes"), this);
 	connect(m_terminal_numbering, &QAction::triggered, this, &QETDiagramEditor::slot_terminalNumbering);
@@ -892,6 +904,7 @@ void QETDiagramEditor::setUpMenu()
 	menu_project -> addAction(m_terminal_strip_dialog);
 	menu_project -> addAction(m_project_terminalBloc);
 	menu_project -> addAction(m_project_export_wiring_list);
+	menu_project -> addAction(m_project_wiring_list_view);
 	menu_project -> addAction(m_terminal_numbering);
 #ifdef QET_EXPORT_PROJECT_DB
 	menu_project -> addSeparator();
@@ -1680,6 +1693,7 @@ void QETDiagramEditor::slot_updateActions()
 	m_project_export_conductor_num-> setEnabled(opened_project);
 	m_terminal_strip_dialog       -> setEnabled(editable_project);
 	m_project_export_wiring_list  -> setEnabled(opened_project);
+	m_project_wiring_list_view    -> setEnabled(opened_project);
 	m_terminal_numbering          -> setEnabled(editable_project);
 #ifdef QET_EXPORT_PROJECT_DB
 	m_export_project_db           -> setEnabled(editable_project);