v3: added a roles/permissions system, added user management tab on user profile

api/db/migrations/0004_user_roles.ts

@@ -0,0 +1,22 @@
+import type { DatabaseSync } from "node:sqlite";
+
+// Idempotent: safe to run against a fresh db (already created from schema.sql
+// with the `role` column) or an existing one that predates it.
+export function up(db: DatabaseSync): void {
+  const userCols = db.prepare(`PRAGMA table_info(users);`).all() as {
+    name: string;
+  }[];
+  if (!userCols.some((c) => c.name === "role")) {
+    db.exec(
+      `ALTER TABLE users ADD COLUMN role TEXT NOT NULL DEFAULT 'user';`,
+    );
+  }
+
+  // Backfill existing admins to role 'admin'. Guarded because the legacy
+  // is_admin column is absent on fresh databases (and dropped by 0005).
+  if (userCols.some((c) => c.name === "is_admin")) {
+    db.exec(
+      `UPDATE users SET role = 'admin' WHERE is_admin = 1 AND role != 'admin';`,
+    );
+  }
+}