Remember unavailable movies and auto-grab them later (wishlist)

When Smart Search finds no good copy of a movie (unreleased / only CAMs), we
now record it instead of dropping it:
- New Wanted model + migration (dedup by tmdbId, status wanted|fulfilled).
- POST /__api/search/releases remembers a movie when it returns no options,
  and the UI confirms it was added to the wishlist.
- controller/wantedWatcher re-runs Smart Search for wishlisted items every 6h
  (and on boot); when a good copy appears it queues the recommended release,
  which then flows through the normal download + organize pipeline, and marks
  the item fulfilled.
- GET/DELETE /__api/search/wanted to view/remove the wishlist.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

models/sql/migrations/20260707120000-create-wanted.js

@@ -0,0 +1,23 @@
+'use strict';
+/** @type {import('sequelize-cli').Migration} */
+module.exports = {
+  async up(queryInterface, Sequelize) {
+    await queryInterface.createTable('Wanteds', {
+      tmdbId: {
+        type: Sequelize.STRING,
+        primaryKey: true,
+        allowNull: false,
+      },
+      mediaType: { type: Sequelize.STRING, allowNull: false, defaultValue: 'movie' },
+      title: { type: Sequelize.STRING },
+      year: { type: Sequelize.STRING },
+      status: { type: Sequelize.STRING, allowNull: false, defaultValue: 'wanted' },
+      requestedBy: { type: Sequelize.STRING },
+      createdAt: { allowNull: false, type: Sequelize.DATE },
+      updatedAt: { allowNull: false, type: Sequelize.DATE },
+    });
+  },
+  async down(queryInterface, Sequelize) {
+    await queryInterface.dropTable('Wanteds');
+  }
+};