Add a live status panel between the run screen's halves

Replaces the small target-HR pill on the iPhone run screen with a
glanceable big-digit strip between the timer flow and the figure —
heart rate (band-tinted with the cue arrow when the run carries a
target), HR zone, active calories, and the workout stopwatch. A
horizontal band in portrait, a vertical column in landscape (the
inverse of the half-and-half split, so it always sits between them).

The watch now rides the running calorie total and the HR zone (1-5,
computed watch-side where max HR is known) along with each live HR
sample; absent keys keep older builds wire-compatible both ways.
LiveRunState holds all three under the shared staleness expiry. The
screenshot rig seeds believable values so the run capture shows the
panel populated.

Workouts/Connectivity/LiveRunState.swift

@@ -40,17 +40,30 @@ final class LiveRunState {
     /// the watch stops sending (session ended, unreachable).
     private(set) var heartRate: Double?
 
+    /// Running active-calorie total for the watch session, riding along with each HR
+    /// sample. Nil until the first energy sample (or from an older watch build).
+    private(set) var activeEnergyKcal: Double?
+
+    /// HR zone (1–5) the current rate falls in, computed on the watch (the only place
+    /// that knows max HR). Nil when the wearer's age is unknown.
+    private(set) var hrZone: Int?
+
     private var heartRateExpiry: Task<Void, Never>?
     private static let hrStaleAfter: Duration = .seconds(30)
 
-    /// Apply an incoming heart-rate sample and (re)arm its staleness expiry.
-    func applyHeartRate(_ bpm: Double) {
+    /// Apply an incoming live sample and (re)arm the shared staleness expiry — the
+    /// three values arrive together, so they go stale together.
+    func applyLiveSample(bpm: Double, kcal: Double?, zone: Int?) {
         heartRate = bpm
+        activeEnergyKcal = kcal
+        hrZone = zone
         heartRateExpiry?.cancel()
         heartRateExpiry = Task { [weak self] in
             try? await Task.sleep(for: Self.hrStaleAfter)
             guard !Task.isCancelled else { return }
             self?.heartRate = nil
+            self?.activeEnergyKcal = nil
+            self?.hrZone = nil
         }
     }