003 handle pool tracking

// Test: Handle pool tracks opened resources
// Resources with <state!> are added to handle pool
// Response includes active handles

~import std/runtime
~import std/io

const std = @import("std");

// Open creates an obligation on the branch payload. Two branches: a lone
// payload branch is a bare return by ruling, and a bare return's obligation
// is not seen by the registry's obligation extraction today.
~pub tor open { path: string }
| opened string<opened!>
| missing

~proc open|zig {
    _ = path;
    return .{ .opened = "file_1" };
}

// Close discharges the obligation
~pub tor close { handle: string<!opened> }

~proc close|zig {
}

// Register scope - compiler infers close is discharge for open
~std/runtime:register(scope: "test") {
    open(10)
    close(1)
}

const TEST_SOURCE = "open(path: \"test.txt\")";

// Open a file, don't close - should be in handle pool
~std/runtime:run(source: TEST_SOURCE, scope: "test", budget: 100, auto_discharge: false)
| result r |> std/io:print.ln("PASS: handles tracked: {{ r.handles:d }}")
| exhausted _ |> std/io:print.ln("FAIL: should not exhaust")
| parse-error _ |> std/io:print.ln("PARSE ERROR")
| validation-error _ |> std/io:print.ln("VALIDATION ERROR")
| shape-error _ |> std/io:print.ln("SHAPE ERROR")
| event-denied _ |> std/io:print.ln("EVENT DENIED")
| dispatch-error _ |> std/io:print.ln("DISPATCH ERROR")
| scope-not-found _ |> std/io:print.ln("SCOPE NOT FOUND")