004 nested router

// ============================================================================
// REGRESSION TEST - Nested Router (Tree-Structured Routing)
// ============================================================================
// Test: Can orisha:router be nested inside another orisha:router's catch-all?
// This is the foundation for tree-structured routing where:
//   ~orisha:router(req)
//   | [GET /api/health] |> response { ... }
//   | [*] |> orisha:router(req)        <-- nested router
//       | [GET /other] |> response { ... }
//       | [*] |> response { ... }       <-- inner catch-all
// ============================================================================

~import "$orisha"
~import "$std/io"

const std = @import("std");

const TestRequest = struct {
    method: []const u8,
    path: []const u8,
};

// Test 1: Hits outer route
const req1 = TestRequest{ .method = "GET", .path = "/api/health" };

~orisha:router(req: &req1)
| [GET /api/health] |> std.io:print.ln("outer: /api/health")
| [*] |> orisha:router(req: &req1)
    | [GET /other] |> std.io:print.ln("inner: /other")
    | [*] |> std.io:print.ln("inner: catch-all")

// Test 2: Falls through to inner route
const req2 = TestRequest{ .method = "GET", .path = "/other" };

~orisha:router(req: &req2)
| [GET /api/health] |> std.io:print.ln("outer: /api/health")
| [*] |> orisha:router(req: &req2)
    | [GET /other] |> std.io:print.ln("inner: /other")
    | [*] |> std.io:print.ln("inner: catch-all")

// Test 3: Falls through to inner catch-all
const req3 = TestRequest{ .method = "POST", .path = "/unknown" };

~orisha:router(req: &req3)
| [GET /api/health] |> std.io:print.ln("outer: /api/health")
| [*] |> orisha:router(req: &req3)
    | [GET /other] |> std.io:print.ln("inner: /other")
    | [*] |> std.io:print.ln("inner: catch-all")