feat: add tag and posts db init

scripts/data/etude.png

scripts/data/folder.png

scripts/data/la_carniere.png

scripts/data/nec.png

scripts/ghost/migrations/init/posts.json

scripts/ghost/migrations/init/tags.json

scripts/init-ghost.js

src/posts/posts.controller.ts

src/posts/posts.service.ts

src/posts/schemas/tag.schema.ts

template.env