feat(driver): add escape to the pressKey surface

escape is a key a spec has real use for and no platform could send it. android maps it to KEYCODE_ESCAPE, the ios companion to HID usage 41 and the in-simulator runner to XCUIKeyboardKey.escape, and the Key union accepts it so it can be written at all.

internal/driver/ioscompanion/presskey_test.go

@@ -0,0 +1,47 @@
+package ioscompanion
+
+import (
+	"context"
+	"testing"
+
+	"github.com/priyanshujain/sanderling/internal/driver/ioscompanion/transport"
+)
+
+// keyRecordingCompanion keeps the HID events a press produced, so the assertion
+// is over what reached the transport rather than over the lookup that built it.
+type keyRecordingCompanion struct {
+	fakeCompanion
+	events []transport.HIDEvent
+}
+
+func (c *keyRecordingCompanion) SendHID(
+	_ context.Context,
+	events ...transport.HIDEvent,
+) error {
+	c.events = append(c.events, events...)
+	return nil
+}
+
+// docs/manual/spec-language.md documents escape, and the simulator's HID stream
+// carries it: usage 41 is the keyboard escape. Without it a spec clause over
+// escape reports unsupported on iOS while the same clause runs on web.
+func TestPressKeyEscapeReachesTheHIDStream(t *testing.T) {
+	companion := &keyRecordingCompanion{}
+	d := newTestDriver(companion)
+
+	if err := d.PressKey(context.Background(), "escape"); err != nil {
+		t.Fatalf("PressKey escape: %v", err)
+	}
+
+	// 41 is the USB HID keyboard escape usage, stated here rather than read
+	// from the production table so a wrong table entry cannot agree with itself.
+	want := []transport.HIDEvent{transport.KeyDown(41), transport.KeyUp(41)}
+	if len(companion.events) != len(want) {
+		t.Fatalf("sent %v, want %v", companion.events, want)
+	}
+	for index, event := range companion.events {
+		if event != want[index] {
+			t.Fatalf("sent %v, want %v", companion.events, want)
+		}
+	}
+}