[Feature?]: File-based routing for middlewares

[Sleepful]

Duplicates

• [x] I have searched the existing issues

Latest version

• [x] I have tested the latest version

Summary 💡

Middlewares that run only on a given route, with file-based routing. The file rules would be similar to those of a layout that works on all routes of a given directory.

A good example can be seen in the Fresh framework, this is a good reference of the feature:

https://fresh.deno.dev/docs/concepts/middleware

Examples 🌈

No response

Motivation 🔦

No response

[Sleepful]

Tangentially related issue: https://github.com/solidjs/solid-start/issues/1811