Motivation

• The GitHub Pages build was failing with Unexpected option config.kit.trailingSlash because newer SvelteKit no longer accepts kit.trailingSlash in svelte.config.js.
• The change preserves the intended routing behavior (always include trailing slashes) while making the config compatible with current SvelteKit.

Description

• Removed the unsupported trailingSlash key from kit in svelte.config.js.
• Added export const trailingSlash = 'always'; to src/routes/+layout.ts to apply the same trailing-slash behavior at the route level.
• Kept appDir: 'assets' and the rest of the kit configuration unchanged.

Testing

• Ran npm run build after the change and the SvelteKit config parsing error for kit.trailingSlash no longer occurred, but the build aborted later due to a missing optional Rollup native binary in this environment.
• Ran npm i to try to repair dependencies and received a 403 Forbidden from the npm registry, preventing a successful full build in this environment.

Codex Task