Have got post creation working.

sql/queries/posts.sql

@@ -0,0 +1,14 @@
+-- name: ListPosts :many
+SELECT * FROM post WHERE site_id = $1 ORDER BY post_date DESC LIMIT 25;
+
+-- name: InsertPost :one
+INSERT INTO post (
+    site_id,
+    title,
+    body,
+    state,
+    props,
+    post_date,
+    created_at
+) VALUES ($1, $2, $3, $4, $5, $6, $7)
+RETURNING id;