Add static attributes and unit tests for Live Activity types

SDK_PROPOSAL.md

@@ -27,6 +27,13 @@ An SDK cannot provide a universal ActivityAttributes type because:
 2. The widget extension must compile the type to render the UI.
 3. Different apps have different Live Activity use cases.
 
+ActivityAttributes have two parts:
+- **Static properties** (on the struct itself) — set at creation, immutable for
+  the activity's lifetime. Example: `name: String`. Included in push-to-start
+  payloads but NOT in update payloads.
+- **ContentState** (nested struct) — changes over time via updates. This is what
+  the server sends in the `content-state` push payload field.
+
 An app can define **multiple** ActivityAttributes types. Each one gets:
 - Its own push-to-start token (per-type, per-device)
 - Its own per-instance activity push tokens
@@ -184,6 +191,41 @@ await Teak.endLiveActivity(activity, content: content, dismissalPolicy: .immedia
 Token revocation on end is particularly important. Stale tokens cause APNs
 delivery failures and waste the app's push notification budget.
 
+## Verified Requirements for Push-to-Start
+
+Discovered during testing with a live device and the Teak backend:
+
+1. **`alert` is required for start events.** Without it, APNs returns 200 but
+   the system silently drops the push. The alert triggers the user-visible
+   notification that creates the activity. Update and end events do not require
+   an alert.
+
+2. **`NSSupportsLiveActivitiesFrequentUpdates` must be `YES` in Info.plist.**
+   Without this flag, push-to-start delivery was inconsistent — sometimes
+   working, sometimes silently dropped. With the flag set, delivery is
+   reliable. This flag grants a higher push update budget; users can disable
+   it in Settings (which ends all ongoing Live Activities).
+
+3. **Date encoding uses `deferredToDate` (Swift's default).** The `endDate`
+   field encodes as `timeIntervalSinceReferenceDate` (seconds since Jan 1,
+   2001 UTC), which is a plain number in JSON. This was verified working.
+   Example: `5.minutes.from_now.to_f - Time.utc(2001,1,1).to_f` in Ruby.
+
+4. **`content-state` must include ALL ContentState fields.** If any field is
+   missing, the Live Activity shows a non-animating loading spinner instead
+   of the expected UI — effectively a crash. The system does not fall back to
+   defaults or show an error; it just hangs. This makes schema validation on
+   the server side critical.
+
+### SDK Implications
+
+- The SDK must document that apps need both `NSSupportsLiveActivities` and
+  `NSSupportsLiveActivitiesFrequentUpdates` in their Info.plist.
+- Start payloads must always include an `alert` — the SDK/backend should
+  enforce this or provide a default.
+- The backend must encode Date fields using `timeIntervalSinceReferenceDate`,
+  not ISO 8601 or Unix timestamps.
+
 ## Push Payload Reference
 
 ### Update Payload
@@ -194,7 +236,7 @@ delivery failures and waste the app's push notification budget.
     "timestamp": 1705560370,
     "event": "update",
     "content-state": {
-      "endDate": "2025-01-18T12:06:10Z",
+      "endDate": 799497600.0,
       "status": "Almost Done!"
     },
     "stale-date": 1705567570,
@@ -208,18 +250,25 @@ delivery failures and waste the app's push notification budget.
 
 ### Start Payload (push-to-start, iOS 17.2+)
 
+**`alert` is REQUIRED for start events** — without it the push is silently dropped.
+
 ```json
 {
   "aps": {
     "timestamp": 1705547770,
     "event": "start",
-    "attributes-type": "TimerActivityAttributes",
-    "attributes": {},
+    "attributes-type": "CountdownActivityAttributes",
+    "attributes": {
+      "name": "My Countdown"
+    },
     "content-state": {
-      "endDate": "2025-01-18T12:06:10Z",
-      "status": "In Progress"
+      "endDate": 799497600.0,
+      "phase": "Remotely Started"
     },
-    "alert": { "title": "...", "body": "..." }
+    "alert": {
+      "title": "Countdown Started",
+      "body": "A countdown was started remotely"
+    }
   }
 }
 ```
@@ -232,7 +281,7 @@ delivery failures and waste the app's push notification budget.
     "timestamp": 1705560370,
     "event": "end",
     "content-state": {
-      "endDate": "2025-01-18T12:06:10Z",
+      "endDate": 799497600.0,
       "status": "Complete"
     },
     "dismissal-date": 1705567570

Shared/CountdownActivityAttributes.swift

@@ -21,5 +21,6 @@ struct CountdownActivityAttributes: ActivityAttributes {
         var phase: String
     }
 
-    // No static properties for this demo.
+    /// Static attributes — set at creation, immutable for the activity's lifetime.
+    var name: String
 }

Shared/TimerActivityAttributes.swift

@@ -14,17 +14,13 @@ struct TimerActivityAttributes: ActivityAttributes {
     /// JSON field in the APNs payload. The JSON keys must exactly match these
     /// property names (or their CodingKeys if customized).
     struct ContentState: Codable, Hashable {
-        /// The time when the timer expires. The widget uses this with
-        /// Text(timerInterval:) to render an auto-updating countdown.
-        var endDate: Date
-
         /// A human-readable status string displayed alongside the timer.
         var status: String
     }
 
-    // No static (per-activity) properties for this demo.
-    // In a real app, you might have something like:
-    //   var activityName: String
-    //   var userId: String
-    // These are set once at activity creation and never change.
+    /// Static attributes are set at creation time and cannot change for the
+    /// lifetime of the activity. Both local starts and push-to-start payloads
+    /// provide these values. The widget extension can reference them alongside
+    /// the dynamic ContentState.
+    var name: String
 }

TeakLiveActivityWidget/CountdownLiveActivity.swift

@@ -7,7 +7,7 @@ import SwiftUI
 struct CountdownLiveActivity: Widget {
     var body: some WidgetConfiguration {
         ActivityConfiguration(for: CountdownActivityAttributes.self) { context in
-            CountdownLockScreenView(state: context.state)
+            CountdownLockScreenView(name: context.attributes.name, state: context.state)
         } dynamicIsland: { context in
             DynamicIsland {
                 DynamicIslandExpandedRegion(.leading) {
@@ -42,12 +42,13 @@ struct CountdownLiveActivity: Widget {
 /// Lock Screen view for countdown activities. Blue background visually
 /// distinguishes this from timer activities (red).
 struct CountdownLockScreenView: View {
+    let name: String
     let state: CountdownActivityAttributes.ContentState
 
     var body: some View {
         HStack {
             VStack(alignment: .leading, spacing: 4) {
-                Label("Countdown", systemImage: "hourglass")
+                Label(name, systemImage: "hourglass")
                     .font(.headline)
                     .foregroundStyle(.white)
 

TeakLiveActivityWidget/TimerLiveActivity.swift

@@ -11,7 +11,7 @@ struct TimerLiveActivity: Widget {
     var body: some WidgetConfiguration {
         ActivityConfiguration(for: TimerActivityAttributes.self) { context in
             // Lock Screen / banner presentation
-            TimerLockScreenView(state: context.state)
+            TimerLockScreenView(name: context.attributes.name, state: context.state)
         } dynamicIsland: { context in
             // Dynamic Island is required by the API even on devices without
             // Dynamic Island hardware. Provides fallback presentations.
@@ -21,22 +21,18 @@ struct TimerLiveActivity: Widget {
                         .font(.caption)
                 }
                 DynamicIslandExpandedRegion(.trailing) {
-                    Text(timerInterval: Date.now...context.state.endDate, countsDown: true)
+                    Text(context.state.status)
                         .font(.caption)
-                        .monospacedDigit()
                 }
                 DynamicIslandExpandedRegion(.bottom) {
-                    Text(context.state.status)
-                        .font(.caption2)
+                    EmptyView()
                 }
             } compactLeading: {
                 Image(systemName: "timer")
                     .foregroundStyle(.red)
             } compactTrailing: {
-                Text(timerInterval: Date.now...context.state.endDate, countsDown: true)
-                    .monospacedDigit()
+                Text(context.state.status)
                     .font(.caption)
-                    .frame(width: 44)
             } minimal: {
                 Image(systemName: "timer")
                     .foregroundStyle(.red)
@@ -48,12 +44,13 @@ struct TimerLiveActivity: Widget {
 /// Lock Screen view for timer activities. Red background visually
 /// distinguishes this from countdown activities (blue).
 struct TimerLockScreenView: View {
+    let name: String
     let state: TimerActivityAttributes.ContentState
 
     var body: some View {
         HStack {
             VStack(alignment: .leading, spacing: 4) {
-                Label("Timer", systemImage: "timer")
+                Label(name, systemImage: "timer")
                     .font(.headline)
                     .foregroundStyle(.white)
 
@@ -63,10 +60,6 @@ struct TimerLockScreenView: View {
             }
 
             Spacer()
-
-            Text(timerInterval: Date.now...state.endDate, countsDown: true)
-                .font(.system(size: 36, weight: .bold, design: .monospaced))
-                .foregroundStyle(.white)
         }
         .padding()
         .background(.red.gradient)