fix: comprehensive boot warnings and exceptions — fixable silenced, unfixable diagnosed

Build system (5 gaps hardened):
- COOKBOOK_OFFLINE defaults to true (fork-mode)
- normalize_patch handles diff -ruN format
- New 'repo validate-patches' command (25/25 relibc patches)
- 14 patched Qt/Wayland/display recipes added to protected list
- relibc archive regenerated with current patch chain

Boot fixes (fixable):
- Full ISO EFI partition: 16 MiB → 1 MiB (matches mini, BIOS hardcoded 2 MiB offset)
- D-Bus system bus: absolute /usr/bin/dbus-daemon path (was skipped)
- redbear-sessiond: absolute /usr/bin/redbear-sessiond path (was skipped)
- daemon framework: silenced spurious INIT_NOTIFY warnings for oneshot_async services (P0-daemon-silence-init-notify.patch)
- udev-shim: demoted INIT_NOTIFY warning to INFO (expected for oneshot_async)
- relibc: comprehensive named semaphores (sem_open/close/unlink) replacing upstream todo!() stubs
- greeterd: Wayland socket timeout 15s → 30s (compositor DRM wait)
- greeter-ui: built and linked (header guard unification, sem_compat stubs removed)
- mc: un-ignored in both configs, fixed glib/libiconv/pcre2 transitive deps
- greeter config: removed stale keymapd dependency from display/greeter services
- prefix toolchain: relibc headers synced, _RELIBC_STDLIB_H guard unified

Unfixable (diagnosed, upstream):
- i2c-hidd: abort on no-I2C-hardware (QEMU) — process::exit → relibc abort
- kded6/greeter-ui: page fault 0x8 — Qt library null deref
- Thread panics fd != -1 — Rust std library on Redox
- DHCP timeout / eth0 MAC — QEMU user-mode networking
- hwrngd/thermald — no hardware RNG/thermal in VM
- live preload allocation — BIOS memory fragmentation, continues on demand

local/recipes/qt/qtwayland/source/examples/wayland/minimal-qml/doc/src/minimal-qml.qdoc

@@ -0,0 +1,93 @@
+// Copyright (C) 2021 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
+
+/*!
+ * \title Minimal QML
+ * \example minimal-qml
+ * \examplecategory {Embedded}
+ * \brief Minimal QML is a simple example that demonstrates how to write a Wayland compositor in QML.
+ * \ingroup qtwaylandcompositor-examples
+ *
+ * Minimal QML is a desktop-style Wayland compositor example implementing a
+ * complete Qt Wayland Compositor with as little code as possible. The compositor is implemented
+ * with Qt Quick and QML.
+ *
+ * \image minimal-qml.png
+ *
+ * \section1 The WaylandCompositor Object
+ *
+ * The top-level item of the compositor is a \l WaylandCompositor. This represents the Wayland
+ * server itself and manages the connections to clients as they come in.
+ *
+ * \snippet minimal-qml/main.qml compositor
+ *
+ * By default, the server supports the core Wayland protocol for communicating with clients.
+ * Usually, though, you will also want to support one or more extensions to the protocol. This
+ * gives the client more tools to influence its role in the windowing system.
+ *
+ * Qt supports several standard and common extensions. In addition, it is easy to create and support
+ * custom extensions, as long as support can be added in both the client and server code.
+ *
+ * \section1 Shell Extensions
+ *
+ * Typically, a compositor will support at least one
+ * \l{Shell Extensions - Qt Wayland Compositor}{shell extension}. Extensions are added to
+ * the compositor by instantiating them as direct children of the \l WaylandCompositor object. They
+ * will automatically be added to its \c extensions property and broadcast to clients when they
+ * connect.
+ *
+ * \snippet minimal-qml/main.qml shells
+ *
+ * The \e{Minimal QML} example supports three different shells: \l{WlShell}, \l{XdgShell} and
+ * \l{IviApplication}.
+ *
+ * A client can connect to either of these and it will be used as a channel for communicating
+ * about certain things between the client and compositor, such as creating new windows,
+ * negotiating size, and so on.
+ *
+ * When a client creates a new surface, its active extension will receive a signal of this. The
+ * signal contains a \l ShellSurface argument. Depending on which extension received the signal,
+ * this argument will be of a subclass of \l{ShellSurface}: \l{WlShellSurface}, \l{XdgSurface}
+ * or \l{IviSurface} respectively.
+ *
+ * The \l ShellSurface can be used to access features of the shell extension for the specific
+ * surface. In the \e{Minimal QML} example, we simply want to add the client to our scene. To
+ * record existence of the new window, we add it to a simple \l ListModel for safe-keeping.
+ *
+ * \snippet minimal-qml/main.qml model
+ *
+ * \section1 Creating the Scene
+ *
+ * Most of the necessary compositor code is already ready. The final step is to make sure
+ * applications are actually visible on the screen.
+ *
+ * For all compositors, we have to define at least one output. This is done by instantiating
+ * a \l WaylandOutput object as the direct child of the \l WaylandCompositor. If there is only
+ * a single output, this will represent the primary screen on the system. (You may also create
+ * multiple \l WaylandOutput objects to address multiple screens if they are available. See
+ * the \l{Multi Screen}{Multi Screen example} for more details
+ * about this.)
+ *
+ * \snippet minimal-qml/main.qml output
+ *
+ * Inside the \l{WaylandOutput}, we create a \l Window that serves as the container for
+ * our scene. In the example, we give this a size. The size used if the compositor is running as
+ * an application inside another windowing system which supports custom-sized windows. In a
+ * typical use case on an embedded device, where the compositor is the only display server running,
+ * it will probably be running on a full-screen platform plugin (such as \c{eglfs}) and the size
+ * set here will not matter.
+ *
+ * The final step is to create items for each of the \l ShellSurface objects that have been created.
+ * For this, we can use the \l ShellSurfaceItem class.
+ *
+ * \snippet minimal-qml/main.qml shell surface item
+ *
+ * We create a \l ShellSurfaceItem for each of the shell surfaces in our model, and assign them
+ * to the \c shellSurface property. In addition, we make sure the model is updated when the shell
+ * surface is destroyed. This can happen when a client manually closes a window, and if it exits
+ * or crashes.
+ *
+ * And this is all the code needed to create a functional Wayland compositor using Qt Quick and
+ * QML. For another example of a compositor written in QML but which has a few more features, take
+ * a look at the \l{Fancy Compositor}{Fancy Compositor example}.
+ */