feat: implement feed agg and browse

sql/queries/posts.sql

@@ -0,0 +1,33 @@
+-- name: CreatePost :one
+INSERT INTO posts (id, created_at, updated_at, title, url, description, published_at, feed_id)
+VALUES (
+  $1,
+  $2,
+  $3,
+  $4,
+  $5,
+  $6,
+  $7,
+  $8
+)
+RETURNING *;
+
+-- name: GetPostsForUser :many
+SELECT 
+  posts.id, 
+  posts.created_at, 
+  posts.updated_at, 
+  posts.title, 
+  posts.url, 
+  posts.description, 
+  posts.published_at, 
+  posts.feed_id,
+  feeds.name as feed_name
+FROM posts
+INNER JOIN feeds
+  ON posts.feed_id = feeds.id
+INNER JOIN follows
+  ON posts.feed_id = follows.feed_id
+WHERE follows.user_id = $1
+ORDER BY posts.published_at DESC, posts.title ASC
+LIMIT $2;