Implement migrations, and switch from sqlx to rusqlite

migrations/01-create-users-table/up.sql

@@ -0,0 +1,36 @@
+-- {{{ users
+create table IF NOT EXISTS users (
+    id INTEGER NOT NULL PRIMARY KEY,
+    discord_id TEXT UNIQUE NOT NULL,
+    is_pookie BOOL NOT NULL DEFAULT 0
+);
+-- }}}
+-- {{{ plays
+CREATE TABLE IF NOT EXISTS plays (
+    id INTEGER NOT NULL PRIMARY KEY,
+    chart_id INTEGER NOT NULL,
+    user_id INTEGER NOT NULL,
+    discord_attachment_id TEXT,
+
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    max_recall INTEGER,
+    far_notes INTEGER,
+
+    FOREIGN KEY (chart_id) REFERENCES charts(id),
+    FOREIGN KEY (user_id) REFERENCES users(id)
+);
+-- }}}
+-- {{{ scores
+CREATE TABLE IF NOT EXISTS scores (
+   id INTEGER NOT NULL PRIMARY KEY,
+   play_id INTEGER NOT NULL,
+
+   score INTEGER NOT NULL,
+   creation_ptt INTEGER,
+   scoring_system TEXT NOT NULL CHECK (scoring_system IN ('standard', 'sdf', 'ex')),
+
+   FOREIGN KEY (play_id) REFERENCES plays(id),
+   UNIQUE(play_id, scoring_system)
+)
+-- }}}