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.

.gitignore

@@ -4,8 +4,13 @@
 !.env.example
 
 # Local runtime data (SQLite + 加密密钥)
+# 2026-11-04 起真身已迁到 /root/apps/ai-image-data/（git 工作树外）。
+# 这里的 data/ output/ 只保留为指向新位置的符号链接（方便老路径继续用）。
 data/
 output/
+# 符号链接本身也别提交（目录形式的规则匹配不到 symlink）
+/data
+/output
 .screenshots/
 .trae-html-share-packages/