Phase 3 sub-commit 3: examples/todo POC app, built via the makers

Standalone Composer/CMake project under examples/todo/ derived from the
skeleton, demonstrating every Phase 3 architectural primitive in a
non-trivial app. All cross-side wiring is maker-generated; no
handwritten bridge glue.

Generated and customised:

  - src/Entity/Todo.php — make:bridge:resource Todo (UUIDv7 id)
  - src/Controller/TodoController.php — make:bridge:resource Todo (CRUD)
  - src/Controller/MarkAllDoneController.php — make:bridge:command
    MarkAllDone, body filled in to flip done=true on every row
  - qml/TodoList.qml — make:bridge:resource Todo (starter ListView)
  - qml/TodoWindow.qml — make:bridge:window Todo, body customised to
    embed a read-only mirror of the same ReactiveListModel

The Phase 1 ping demo is dropped from this app — it doesn't fit the
todo flow and nothing in Main.qml references it.

Main.qml is the real list UI:

  - Add input + button (POST /api/todos with optimistic-friendly key).
  - Per-row CheckBox + delete button (PATCH/DELETE via
    todoModel.invoke() with `pending` role driving opacity).
  - "Mark all done" button (POST /api/mark-all-done).
  - "Open second window" button (Component { TodoWindow {} } pattern).

Build / run delegated to the same Makefile shape as the skeleton, with
SCRIPT_DIR/QT_BIN updated for the renamed binary (build/qml/todo).
composer.json's path repo points at ../../../framework/php (one level
deeper than the skeleton's path repo).

Verified end-to-end with offscreen QPA: POST/PATCH/DELETE on /api/todos
all round-trip, /api/mark-all-done flips every row, Mercure dual-
publishes on every change. Clean shutdown.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

examples/todo/qml/TodoWindow.qml

@@ -0,0 +1,75 @@
+// Auto-generated by `bin/console make:bridge:window Todo`,
+// then customised to embed a read-only TodoList. Independently subscribed
+// to the same Mercure topic — proves the multi-window test in PLAN.md §13.
+
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import QtQuick.Window
+import PhpQml.Bridge
+
+ApplicationWindow {
+    id: todoWindow
+    width: 480
+    height: 520
+    visible: true
+    title: "Todos (mirror)"
+
+    ReactiveListModel {
+        id: mirrorModel
+        baseUrl: BackendConnection.url
+        token:   BackendConnection.token
+        source:  "/api/todos"
+        topic:   "app://model/todo"
+    }
+
+    AppShell {
+        anchors.fill: parent
+
+        ColumnLayout {
+            anchors.fill: parent
+            anchors.margins: 16
+            spacing: 12
+
+            Label {
+                text: "Mirror window"
+                font.pixelSize: 16
+                font.bold: true
+            }
+            Label {
+                text: "Read-only view of the same /api/todos. Edits in the main window propagate here within ~50 ms via Mercure."
+                wrapMode: Text.Wrap
+                opacity: 0.7
+                Layout.fillWidth: true
+            }
+
+            Frame {
+                Layout.fillWidth: true
+                Layout.fillHeight: true
+                padding: 0
+                ListView {
+                    anchors.fill: parent
+                    clip: true
+                    model: mirrorModel
+
+                    delegate: ItemDelegate {
+                        required property string title
+                        required property bool done
+                        required property bool pending
+
+                        width: ListView.view.width
+                        opacity: pending ? 0.5 : 1.0
+                        text: (done ? "✓ " : "  ") + title
+                    }
+
+                    Label {
+                        anchors.centerIn: parent
+                        visible: parent.count === 0 && mirrorModel.ready
+                        text: "(empty)"
+                        opacity: 0.5
+                    }
+                }
+            }
+        }
+    }
+}