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/PoolMapTests.cpp

@@ -0,0 +1,49 @@
+#include "Document/PixelAdjust.h"
+#include "Rendering/HslBlend.h"
+#include "Rendering/PoolMap.h"
+#include <QtTest>
+#include <atomic>
+#include <cstdio>
+
+// Parallel kernels in a worker finish on a one-thread pool.
+class PoolMapTests : public QObject {
+    Q_OBJECT
+private slots:
+    void aPoolThreadLendsItsPlaceWhileItWaits();
+};
+
+namespace {
+// On the pool; a hang ends the binary, else waiting.
+void finishes(const char *name, const std::function<void()> &work)
+{
+    QFuture<void> job = QtConcurrent::run(work);
+    if (!QTest::qWaitFor([&job] { return job.isFinished(); }, 10'000)) {
+        std::fprintf(stderr, "%s hung on a one-thread pool\n", name);
+        std::_Exit(1);
+    }
+}
+}
+
+void PoolMapTests::aPoolThreadLendsItsPlaceWhileItWaits()
+{
+    QThreadPool *pool = QThreadPool::globalInstance();
+    const int threads = pool->maxThreadCount();
+    pool->setMaxThreadCount(1);
+    QImage image(48, 40, QImage::Format_RGBA8888_Premultiplied);
+    image.fill(qRgba(40, 80, 120, 255));
+    QImage blended, blurred;
+    finishes("the HSL blend", [&] { blended = HslBlend::blend(image, image, LayerBlendMode::hue, 1); });
+    finishes("the Gaussian blur", [&] { blurred = PixelAdjust::gaussianBlur(image, 3, false); });
+    QCOMPARE(blended.size(), image.size());
+    QCOMPARE(blurred.size(), image.size());
+    // The lent place comes back: the pool counts right again.
+    std::atomic<int> seen = 0;
+    std::vector<int> items(64);
+    finishes("a map in a worker", [&] { PoolMap::blocking(items, [&seen](int &) { ++seen; }); });
+    QCOMPARE(seen.load(), 64);
+    QCOMPARE(pool->activeThreadCount(), 0);
+    pool->setMaxThreadCount(threads);
+}
+
+QTEST_GUILESS_MAIN(PoolMapTests)
+#include "PoolMapTests.moc"