Static middleware use prefix (backward compatible)

[thetutlage]

Currently, all HTTP requests pass through the static file middleware and perform a file-existence check on disk. This introduces unnecessary overhead. To improve performance, the static file lookup should only occur when the request URL starts with a predefined prefix such as /public or /assets.

We will maintain backward compatibility by enabling prefix-based checks only when configured (and this will be the default behavior for all new applications).