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/symfony/migrations/Version20260502004612.php

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+/**
+ * Auto-generated Migration: Please modify to your needs!
+ */
+final class Version20260502004612 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return '';
+    }
+
+    public function up(Schema $schema): void
+    {
+        // this up() migration is auto-generated, please modify it to your needs
+        $this->addSql('CREATE TABLE todo (id BLOB NOT NULL, title VARCHAR(255) NOT NULL, done BOOLEAN NOT NULL, PRIMARY KEY (id))');
+    }
+
+    public function down(Schema $schema): void
+    {
+        // this down() migration is auto-generated, please modify it to your needs
+        $this->addSql('DROP TABLE todo');
+    }
+}