Deflake two iOS-sim CI tests with unbounded timing assumptions

Both failed on main-adjacent CI runs during this session's PRs. Neither
was a product bug; both asserted things about real time that a loaded
runner is under no obligation to honour.

**NetworkReachabilityGateTests: a wall-clock upper bound.**
test_monitor_duplicateUpdatesDoNotPostponeOfflineCommit slept 500ms for
real, then asserted total elapsed time was under 1.4s to prove a duplicate
mid-window had not restarted the 1.0s debounce. One CI run took 3.75s. No
wall-clock bound can separate "deadline preserved" from "runner is slow",
because Task.sleep and the asyncAfter flush are both real time and neither
is bounded above.

The deadline property was already covered deterministically one level
down: test_debounce_duplicateObservationsPreservePendingDeadline drives
ReachabilityDebounce with injected timestamps and checks pendingRemaining
directly. So the monitor test now asserts only what needs a real monitor —
that a duplicate still yields exactly one committed false through the
debounce — with an injected clock for the arithmetic and a generous
liveness budget. Renamed to say what it actually checks. No coverage lost,
and it runs in 0.14s instead of ~3.8s because the real sleep is gone.

**NoiseEncryptionServiceTests: injected timeouts that also arm during
setup.** #1483 diagnosed and fixed exactly this in the quarantine-restore
test, but two sibling tests kept the shape. Their injected
ordinaryResponderHandshakeTimeout (0.04 and 0.06) also arms during the
establishSessions setup handshake, where bob is the responder — so a
preempted runner fires it mid-setup, tears down the half-open responder,
and message 3 gets answered as a fresh initiation. The CI failure named
setup's own `#expect(finalMessage == nil)` seeing a 96-byte message 2,
which is precisely the signature #1483 recorded.

Raised both to 1.0s, matching #1483's remedy: the scenarios still need the
responder timeout to fire, and it still does, just with room for setup to
complete first. Thin 1-second waitUntil budgets in the file now use the
shared TestConstants.longTimeout; every one of them backs a positive
assertion, so waitUntil still returns the moment the condition holds and
nothing gets slower in the passing case.

No assertion weakened in either file. Verified 3x sequentially and 3x with
all 18 cores saturated.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

bitchatTests/Services/NetworkReachabilityGateTests.swift

@@ -69,25 +69,45 @@ final class NetworkReachabilityGateTests: XCTestCase {
         XCTAssertNil(d.pendingRemaining(at: t0.addingTimeInterval(2.5)))
     }
 
-    func test_monitor_duplicateUpdatesDoNotPostponeOfflineCommit() async {
-        let monitor = NWPathReachabilityMonitor(debounceInterval: 1.0)
+    /// Wiring only: a duplicate mid-window still yields exactly one committed
+    /// `false`, published through the monitor's debounce.
+    ///
+    /// This deliberately makes no assertion about *when* the flush fires. It
+    /// used to bound elapsed wall-clock time at 1.4 s to prove the deadline was
+    /// not restarted, which flaked on loaded CI runners — one observed run took
+    /// 3.75 s, because `Task.sleep` and the `asyncAfter` flush are both real
+    /// time and neither is bounded above on a busy machine. No wall-clock bound
+    /// can distinguish "deadline preserved" from "runner is slow", so the timing
+    /// property is asserted where it is computable instead:
+    /// `test_debounce_duplicateObservationsPreservePendingDeadline` drives
+    /// `ReachabilityDebounce` with injected timestamps and checks
+    /// `pendingRemaining` directly.
+    ///
+    /// The clock is injected here so the debounce arithmetic is deterministic
+    /// even though the flush itself is scheduled in real time.
+    func test_monitor_duplicateUpdatesCommitOnceThroughTheDebounce() async {
+        let clock = MutableDate(now: Date(timeIntervalSince1970: 1_784_000_000))
+        let monitor = NWPathReachabilityMonitor(
+            debounceInterval: 0.2,
+            now: { clock.now }
+        )
         var received: [Bool] = []
         let cancellable = monitor.reachabilityPublisher.sink { received.append($0) }
         defer { cancellable.cancel() }
 
-        let start = Date()
         monitor.ingest(reachable: false)
-        try? await Task.sleep(nanoseconds: 500_000_000)
-        // Duplicate unsatisfied update mid-window (e.g. interface detail change
-        // while still offline) must not restart the debounce window.
+        // Duplicate unsatisfied update mid-window (e.g. an interface detail
+        // change while still offline).
+        clock.now = clock.now.addingTimeInterval(0.1)
         monitor.ingest(reachable: false)
+        // Past the original deadline, so the scheduled flush commits.
+        clock.now = clock.now.addingTimeInterval(0.2)
 
-        let committed = await waitUntil(timeout: 2.0) { !received.isEmpty }
+        // Generous: this is a liveness check, not a latency bound. A real
+        // regression — never committing — still fails, just later.
+        let committed = await waitUntil(timeout: 10.0) { !received.isEmpty }
         XCTAssertTrue(committed)
         XCTAssertEqual(received, [false])
-        // The flush must fire at the original ~1.0s deadline, not ~1.5s
-        // (a full interval after the duplicate).
-        XCTAssertLessThan(Date().timeIntervalSince(start), 1.4)
     }
 
     // MARK: - Service gating
@@ -239,3 +259,13 @@ private final class GateMockProxyController: NetworkActivationProxyControlling {
     private(set) var proxyModes: [Bool] = []
     func setProxyMode(useTor: Bool) { proxyModes.append(useTor) }
 }
+
+/// Controllable clock, so debounce arithmetic is deterministic even where the
+/// flush itself is scheduled in real time.
+private final class MutableDate: @unchecked Sendable {
+    var now: Date
+
+    init(now: Date) {
+        self.now = now
+    }
+}

bitchatTests/Services/NoiseEncryptionServiceTests.swift

@@ -652,12 +652,12 @@ struct NoiseEncryptionServiceTests {
         )
         let retried = await TestHelpers.waitUntil(
             { recorder.messages.count == 1 },
-            timeout: 1
+            timeout: TestConstants.longTimeout
         )
         #expect(retried)
         let retryExpired = await TestHelpers.waitUntil(
             { !service.hasSession(with: peerID) },
-            timeout: 1
+            timeout: TestConstants.longTimeout
         )
         #expect(retryExpired)
         #expect(recorder.timeoutCount == 1)
@@ -710,7 +710,12 @@ struct NoiseEncryptionServiceTests {
         let alice = NoiseEncryptionService(keychain: MockKeychain())
         let bob = NoiseEncryptionService(
             keychain: MockKeychain(),
-            ordinaryResponderHandshakeTimeout: 0.06,
+            // Generous for the same reason as the quarantine-restore test
+            // (#1483): this timeout also arms during the `establishSessions`
+            // setup handshake below, where bob is the responder. At 0.06 a
+            // preempted runner could fire it mid-setup, tear down the half-open
+            // responder, and make message 3 be answered as a fresh initiation.
+            ordinaryResponderHandshakeTimeout: 1.0,
             ordinaryReconnectRollbackCooldown: 0.3
         )
         let mallory = NoiseEncryptionService(keychain: MockKeychain())
@@ -741,12 +746,12 @@ struct NoiseEncryptionServiceTests {
 
         let restored = await TestHelpers.waitUntil(
             { bob.hasEstablishedSession(with: alicePeerID) },
-            timeout: 1
+            timeout: TestConstants.longTimeout
         )
         #expect(restored)
         let callbackArrived = await TestHelpers.waitUntil(
             { recovery.timeoutCount == 1 },
-            timeout: 1
+            timeout: TestConstants.longTimeout
         )
         #expect(callbackArrived)
 
@@ -780,7 +785,13 @@ struct NoiseEncryptionServiceTests {
         let bob = NoiseEncryptionService(
             keychain: MockKeychain(),
             ordinaryHandshakeTimeout: 0.04,
-            ordinaryResponderHandshakeTimeout: 0.04
+            // Also arms during the `establishSessions` setup handshake below,
+            // where bob is the responder. Observed failing on a loaded CI
+            // runner with exactly the signature #1483 documented: the setup's
+            // `#expect(finalMessage == nil)` saw a 96-byte message 2, because
+            // the half-open responder had already been torn down and message 3
+            // was answered as a fresh initiation.
+            ordinaryResponderHandshakeTimeout: 1.0
         )
         let alicePeerID = PeerID(publicKey: alice.getStaticPublicKeyData())
         let bobPeerID = PeerID(publicKey: bob.getStaticPublicKeyData())
@@ -814,12 +825,12 @@ struct NoiseEncryptionServiceTests {
         // initiates one bounded convergence retry; drop that message 1 too.
         let retryPrepared = await TestHelpers.waitUntil(
             { recovery.messages.count == 1 },
-            timeout: 1
+            timeout: TestConstants.longTimeout
         )
         #expect(retryPrepared)
         let retryExpired = await TestHelpers.waitUntil(
             { !bob.hasSession(with: alicePeerID) },
-            timeout: 1
+            timeout: TestConstants.longTimeout
         )
         #expect(retryExpired)
         #expect(recovery.timeoutCount == 1)
@@ -1026,7 +1037,7 @@ struct NoiseEncryptionServiceTests {
 
         let requested = await TestHelpers.waitUntil(
             { recovery.messages.count == 1 },
-            timeout: 1
+            timeout: TestConstants.longTimeout
         )
         #expect(requested)
         let retryMessage1 = try #require(recovery.messages.first)