Function navigate 

pub fn navigate(path: &str) -> bool

Navigate to a route (docs/navigation.md).

• A single key (navigate("inbox")) is RELATIVE — the innermost route surface is tried first, falling through outward; "" pops the innermost stack to its root.
• A /-separated path (navigate("mail/inbox/msg-42")) is ABSOLUTE — anchored at the outermost surface that knows the first segment, everything inside reset, the remaining segments consumed inward (surfaces mounting during the cascade take theirs as they appear).
• A trailing ?name=value&… carries route_params to the destination builders.

False = no surface recognized the (first) segment.