Add desktop app service and VM dev session tooling

Introduces a new `core/applications` QML/C++ module (`Nebula.Applications`) to discover `.desktop` entries, expose filterable application models, and launch installed apps safely from the shell. The desktop launcher now uses real installed apps with themed icon loading and fallback glyphs, adds output-aware surface sizing via `OutputTracker`, and wires in image/icon providers. It also adds VMware-focused Sway/shell wrapper scripts, updates Sway config/session env defaults, and refreshes README docs to document the new development flow and Desktop 0.1 behavior.

core/applications/ApplicationModel.hpp

@@ -0,0 +1,44 @@
+#pragma once
+
+#include "DesktopEntry.hpp"
+
+#include <QAbstractListModel>
+#include <QVector>
+#include <QtQml/qqmlregistration.h>
+
+class ApplicationModel : public QAbstractListModel
+{
+    Q_OBJECT
+    QML_ELEMENT
+    QML_UNCREATABLE("Obtained from ApplicationService")
+    Q_PROPERTY(int count READ count NOTIFY countChanged)
+
+public:
+    enum Roles {
+        DesktopIdRole = Qt::UserRole + 1,
+        NameRole,
+        GenericNameRole,
+        CommentRole,
+        IconNameRole,
+        CategoriesRole,
+        TerminalRole
+    };
+    Q_ENUM(Roles)
+
+    explicit ApplicationModel(QObject *parent = nullptr);
+
+    int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+    QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
+    QHash<int, QByteArray> roleNames() const override;
+
+    int count() const;
+    void setEntries(QVector<DesktopEntry> entries);
+    const DesktopEntry *entryAt(int row) const;
+    const DesktopEntry *entryById(const QString &desktopId) const;
+
+signals:
+    void countChanged();
+
+private:
+    QVector<DesktopEntry> m_entries;
+};