Attribute Macro context 

#[context]

Transforms a struct with permission-type fields into a capability context.

Generates:

• Field types rewritten from PermType to Cap<PermType> (or SendCap<PermType>)
• A new(root: &CapRoot) -> Self constructor
• impl Has<P> for each field’s permission type

Usage

#[capsec::context]
struct AppCtx {
    fs: FsRead,
    net: NetConnect,
}

// Send variant for async/threaded code:
#[capsec::context(send)]
struct AsyncCtx {
    fs: FsRead,
    net: NetConnect,
}