add initial stuff

internal/db/sql/sessions.sql

@@ -0,0 +1,43 @@
+-- sqlfluff:dialect:sqlite
+-- name: CreateSession :one
+INSERT INTO sessions (
+    id,
+    title,
+    message_count,
+    tokens,
+    cost,
+    updated_at,
+    created_at
+) VALUES (
+    ?,
+    ?,
+    ?,
+    ?,
+    ?,
+    strftime('%s', 'now'),
+    strftime('%s', 'now')
+) RETURNING *;
+
+-- name: GetSessionByID :one
+SELECT *
+FROM sessions
+WHERE id = ? LIMIT 1;
+
+-- name: ListSessions :many
+SELECT *
+FROM sessions
+ORDER BY created_at DESC;
+
+-- name: UpdateSession :one
+UPDATE sessions
+SET
+    title = ?,
+    tokens = ?,
+    cost = ?
+WHERE id = ?
+RETURNING *;
+
+
+-- name: DeleteSession :exec
+DELETE FROM sessions
+WHERE id = ?;