Attribute Macro patchable_model 

#[patchable_model]

Attribute macro that augments a struct with Patchable/Patch derives.

• Always adds #[derive(Patchable, Patch)].
• When the serde feature is enabled for the macro crate, it also adds #[derive(serde::Serialize)].
• For fields annotated with #[patchable(skip)], it injects #[serde(skip)] to keep serde output aligned with patching behavior.

This macro preserves the original struct shape and only mutates attributes.