[Feature] More flex URL management

[xihale]

Hi! Zine is very good to use, and its features impresses me.
However, currently, I'm constrained by the existing subpage features, which leads me to name my files as 2025-06-12-Title.smd. My goal is to have the rendered output URL appear as 2025/06/12/Title/.

I believe Zine could benefit from enhanced URL management options, drawing inspiration from Hugo's management capabilities to provide users with greater freedom