docs(og): record why process.cwd() is the app dir in the container

Review flagged the font path as invalid in the standalone image, reasoning
that the container starts at the monorepo root. It does -- but Next's generated
standalone server.js opens with process.chdir(__dirname), and that file ships
beside public/. Same reason content/ is read this way at runtime.

Author: waleedlatif1

apps/sim/app/(landing)/og-utils.tsx

@@ -36,8 +36,14 @@ function getTitleFontSize(title: string): number {
  * serves to browsers cannot be reused here.
  *
  * These live under `public/` so they need no `outputFileTracingIncludes` entry:
- * the Dockerfile copies that directory into the runner, which the
+ * `docker/app.Dockerfile` copies that directory into the runner, which the
  * `force-dynamic` share-token card needs since it renders per request.
+ *
+ * `process.cwd()` is the app directory in every environment this runs in, not
+ * just dev and build. The container starts at the monorepo root, but Next's
+ * generated standalone `server.js` opens with `process.chdir(__dirname)`, and
+ * that file ships beside `public/` — which is also why `content/` is read this
+ * way at runtime.
  */
 const FONT_DIR = join(process.cwd(), 'public', 'brand', 'fonts')