let client = PrismPermissionClient()
let status = try await client.request(.camera)

if status.isGranted {
    // Open camera
}

let statuses = try await client.request([.camera, .microphone, .photoLibrary])

for (permission, status) in statuses {
    print("\(permission.displayName): \(status)")
}

let status = try await client.check(.contacts)
if status.canRequest {
    // Show rationale UI, then request
}

enum PrismPermissionStatus: Sendable {
    case notDetermined  // canRequest = true
    case authorized     // isGranted = true
    case denied         // canRequest = false
    case restricted     // system-level restriction
    case limited        // isGranted = true (partial access)
    case provisional    // isGranted = true (quiet notifications)
}

let monitor = PrismPermissionMonitor(
    permissions: [.camera, .microphone],
    interval: 2.0
)

for await change in monitor.changes {
    print("\(change.permission) changed: \(change.oldStatus) → \(change.newStatus)")
}

let bio = PrismBiometricAuth()
try await bio.authenticate(reason: "Access your vault")

let type = bio.availableType()  // .faceID, .touchID, .opticID, or .none

if bio.isAvailable() {
    try await bio.authenticate(reason: "Unlock")
}

// Biometrics only — no passcode fallback
try await bio.authenticate(
    reason: "High security action",
    policy: .biometricsOnly
)

// Biometrics or device passcode (default)
try await bio.authenticate(
    reason: "Standard action",
    policy: .biometricsOrPasscode
)

let result = await bio.authenticateResult(reason: "Confirm payment")

switch result {
case .success:
    processPayment()
case .failure(let error):
    showError(error)
}