Seeking advice on minimizing function and worker usage (Nuxt on Cloudflare Pages)

What I want to do:
Deploy brochure site(s) with minimal (or no) cost.

Stack:
Nuxt, Sanity, Cloudflare Pages.

Problem:
$0.00 challenge (maybe I just don't want to pay)

Requirements:

• Trim trailing slash on all routes
• Server-side form sanitation/validation (optional)

Solution 1: Nitro server...
No problem with route middleware, I just don't know this will translate to function/worker usage. Can someone even DoS my site and exhaust 100k allowance? Is it 1 per request? Will crazy convoluted validation logic effect credit used?

Solution 2: Static generation...
I don't know how to use _redirect to trim trailing slash on all routes. The docs do not show any example using wildcard (splat) follow by slash.

Senpai of the Edge, please enlighten me.