:sig
String route_path_sanitize(String path, String default_path = "index")

:see
>uri
route_path_is_safe
route_path_normalize
request_query_path
request_query_route
request_context_params

:content
Normalizes and validates a route path for file-backed routing.

Rules:

- leading and trailing `/` are removed
- an empty path becomes `default_path`
- every path segment must be non-empty
- `.` and `..` segments are rejected
- only ASCII letters, digits, `_`, and `-` are accepted inside a segment
- unsafe input returns an empty string

Use this instead of manually checking app routes before composing file paths.


`request_query_path()`, `request_query_route()`, and the runtime-populated `ROUTE_PATH` params already use this sanitizer.

:example
print(route_path_sanitize("../secret", "index"), "\n");