chore: move generated images and database outside the git worktree

The output/ and data/ directories lived inside this git repo. They are
gitignored, so any rebuild of the directory (git clone into a recreated
path, rm + clone) silently took the generated images and the SQLite
database with it. On 2026-11-04 that cost a full round of regenerated
images.

The real data now lives in /root/apps/ai-image-data/:
  output/  generated images, one subdirectory per profile_name
  data/    ai_image.db + secret.key

Bind mounts use absolute paths so the container never depends on symlink
resolution. ./output and ./data remain as symlinks for backwards
compatibility with existing scripts and skills.

Also ignore the symlinks themselves: the directory-form rules do not
match them, so git would have picked them up.

docker-compose.yml

@@ -8,6 +8,9 @@ services:
     env_file:
       - .env
     volumes:
-      - ./output:/app/output
-      - ./data:/app/data
+      # 生成物与数据库放在 git 工作树外（/root/apps/ai-image 是 git repo，
+      # 目录一旦被 clone/rm 重建，未跟踪的生成物会一起消失 —— 2026-11-04 丢过一轮）。
+      # 用绝对路径而非 ./output，避免 bind mount 跟随符号链接的歧义。
+      - /root/apps/ai-image-data/output:/app/output
+      - /root/apps/ai-image-data/data:/app/data
     restart: unless-stopped