OmaPhoto 1.0.0: the Linux port of Compositor

A layered image editor for Linux and Omarchy, ported from Compositor
(github.com/robbietilton/Compositor), whose Swift source is its
specification. It reads and writes Compositor's .comp projects.

Packages for Ubuntu, Fedora and Arch come from the release workflow;
scripts/install/ holds one install script per distribution family,
and flake.nix serves NixOS.

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

tests/FilterFailureTests.cpp

@@ -0,0 +1,48 @@
+#include "AddressSpaceLimit.h"
+#include "Document/Filters.h"
+#include "Document/PixelAdjust.h"
+#include "IO/ImageExporter.h"
+#include <QPainter>
+#include <QtTest>
+#include <malloc.h>
+
+// The filters' pixels when memory runs out.
+class FilterFailureTests : public QObject {
+    Q_OBJECT
+private slots:
+    void theBlursFailAsAContextWhenTheirRowsFindNoMemory();
+    void aTrimThatFindsNoMemoryIsARenderError();
+};
+
+void FilterFailureTests::theBlursFailAsAContextWhenTheirRowsFindNoMemory()
+{
+    // One pixel wide: its row list asks as its pixels.
+    QImage tall(1, 16'000'000, QImage::Format_RGBA8888_Premultiplied);
+    tall.fill(Qt::red);
+    malloc_trim(0);
+    {
+        // The 64 MB result fits; the rows do not.
+        const AddressSpaceLimit limit(80ll * 1024 * 1024);
+        QVERIFY_THROWS_EXCEPTION(ExportError, PixelAdjust::motionBlur(tall, 1, 0));
+    }
+    malloc_trim(0);
+    {
+        // Result and 256 MB of sums fit; rows do not.
+        const AddressSpaceLimit limit(350ll * 1024 * 1024);
+        QVERIFY_THROWS_EXCEPTION(ExportError, PixelAdjust::gaussianBlur(tall, 1, false));
+    }
+}
+
+void FilterFailureTests::aTrimThatFindsNoMemoryIsARenderError()
+{
+    // Opaque but for its border: the crop copies 96 MB.
+    QImage framed(6000, 4000, QImage::Format_RGBA8888_Premultiplied);
+    framed.fill(Qt::transparent);
+    QPainter(&framed).fillRect(QRect(1, 1, 5998, 3998), Qt::red);
+    malloc_trim(0);
+    const AddressSpaceLimit limit(16ll * 1024 * 1024);
+    QVERIFY_THROWS_EXCEPTION(ExportError, PixelFilter::trimmed(framed, LayerTransform{.origin = {0, 0}, .size = {6000, 4000}}));
+}
+
+QTEST_GUILESS_MAIN(FilterFailureTests)
+#include "FilterFailureTests.moc"