chore: stage all in-progress work before repo split

Web app: new entities (Image, RenderedAsset, SharedImage, Token,
DeviceImageHistory), enums, repositories, controllers, message handlers,
migrations, tests, frontend upload/library/sticker UI, Vue components.

Firmware: EPD background screen binaries + gen scripts, setup_bg header.

Infra: ddev config, test bundle, gitignore coverage dir.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/Entity/Token.php

@@ -0,0 +1,71 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Entity;
+
+use App\Enum\TokenType;
+use App\Repository\TokenRepository;
+use Doctrine\ORM\Mapping as ORM;
+use Symfony\Component\Uid\Uuid;
+
+#[ORM\Entity(repositoryClass: TokenRepository::class)]
+class Token
+{
+    #[ORM\Id]
+    #[ORM\Column(length: 36)]
+    private string $uuid;
+
+    #[ORM\Column(enumType: TokenType::class)]
+    private TokenType $type;
+
+    #[ORM\ManyToOne]
+    #[ORM\JoinColumn(nullable: false, onDelete: 'CASCADE')]
+    private Image $image;
+
+    #[ORM\ManyToOne]
+    #[ORM\JoinColumn(nullable: true, onDelete: 'SET NULL')]
+    private ?User $recipientUser;
+
+    #[ORM\Column(length: 180, nullable: true)]
+    private ?string $recipientEmail;
+
+    #[ORM\Column]
+    private \DateTimeImmutable $expiresAt;
+
+    #[ORM\Column(nullable: true)]
+    private ?\DateTimeImmutable $usedAt = null;
+
+    public function __construct(
+        TokenType $type,
+        Image $image,
+        ?User $recipientUser,
+        ?string $recipientEmail,
+        int $ttlDays,
+    ) {
+        $this->uuid          = Uuid::v4()->toRfc4122();
+        $this->type          = $type;
+        $this->image         = $image;
+        $this->recipientUser = $recipientUser;
+        $this->recipientEmail = $recipientEmail;
+        $this->expiresAt     = new \DateTimeImmutable('+' . $ttlDays . ' days');
+    }
+
+    public function getUuid(): string { return $this->uuid; }
+    public function getType(): TokenType { return $this->type; }
+    public function getImage(): Image { return $this->image; }
+    public function getRecipientUser(): ?User { return $this->recipientUser; }
+    public function getRecipientEmail(): ?string { return $this->recipientEmail; }
+    public function getExpiresAt(): \DateTimeImmutable { return $this->expiresAt; }
+    public function getUsedAt(): ?\DateTimeImmutable { return $this->usedAt; }
+
+    public function isValid(): bool
+    {
+        return $this->usedAt === null && $this->expiresAt > new \DateTimeImmutable();
+    }
+
+    public function consume(): void
+    {
+        $this->usedAt = new \DateTimeImmutable();
+    }
+}