feat: detect seen state, hook up posts API, listen on WS for post changes

.env

package-lock.json

package.json

src/App.jsx

src/actions/posts.js

src/components/Thumbs.jsx

src/components/annoucements/Announcement.jsx

src/components/annoucements/AnnouncementList.jsx

src/components/posts/Post.jsx

src/components/posts/PostList.jsx

src/containers/AnnoucementsContainer.jsx

src/containers/PostsContainer.jsx

src/index.js

src/stores.js

src/utils.js

src/ws/connection.js

src/ws/handlers/index.js

src/ws/handlers/posts.js

typings/cf2021.d.ts