Add contextual help to Array and Save Image dialogs

Explain array counts, offsets, rotations, image dimensions, file naming,
and step ranges with translated tooltips and contextual help. Give both
dialogs a standard Help button and dialog-scoped F1 support that falls back
from the focused control through its parent groups to the overview.

Link image field labels to their buddies and share tooltip and field help
text. Add accessible names for unlabeled controls. Document the writing and
maintenance conventions, with concise guidance in the existing AGENTS.md.

Refresh all eight language catalogs while preserving existing translations
and review status. The 62 new help and accessibility strings remain
unfinished pending translation.

Validation: Qt 6.10 debug build; runtime checks for seven F1 routes, Help,
Escape, dialog state, spin-box focus, and five label buddies with matching
help; visual layout inspection; catalog coverage for all 2,118 active source
messages and existing translation preservation; git diff --check.

common/lc_arraydialog.cpp

@@ -7,6 +7,7 @@ lcArrayDialog::lcArrayDialog(QWidget* Parent)
 	: QDialog(Parent), ui(new Ui::lcArrayDialog)
 {
 	ui->setupUi(this);
+	lcSetupDialogHelp(this, ui->buttonBox);
 
 	ui->offset1x->setValidator(new QDoubleValidator(ui->offset1x));
 	ui->offset1y->setValidator(new QDoubleValidator(ui->offset1y));