chore(test): fix redundant-cast and deprecated Thread.id warnings

Use assertIs in Nip88PollTagsTest instead of assertTrue + a cast the
smart cast already made redundant, and Thread.threadId() in
ObserverListBenchmark in place of the deprecated Thread.id.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MKvUGSMiCwjSdVm33hD4yp

commons/src/jvmTest/kotlin/com/vitorpamplona/amethyst/commons/prodbench/ObserverListBenchmark.kt

@@ -269,7 +269,7 @@ class ObserverListBenchmark {
      */
     private fun allocatedBytes(): Long {
         val bean = ManagementFactory.getThreadMXBean() as com.sun.management.ThreadMXBean
-        return bean.getThreadAllocatedBytes(Thread.currentThread().id)
+        return bean.getThreadAllocatedBytes(Thread.currentThread().threadId())
     }
 
     private fun measureAllocation(
@@ -400,14 +400,14 @@ class ObserverListBenchmark {
             repeat(threads) { t ->
                 thread {
                     start.await()
-                    val before = bean.getThreadAllocatedBytes(Thread.currentThread().id)
+                    val before = bean.getThreadAllocatedBytes(Thread.currentThread().threadId())
                     var i = t
                     while (i < ops) {
                         val (e, note) = fx[i % fx.size]
                         subject.new(e, note)
                         i += threads
                     }
-                    total.addAndGet(bean.getThreadAllocatedBytes(Thread.currentThread().id) - before)
+                    total.addAndGet(bean.getThreadAllocatedBytes(Thread.currentThread().threadId()) - before)
                     done.countDown()
                 }
             }

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip88Polls/Nip88PollTagsTest.kt

@@ -42,6 +42,7 @@ import kotlin.test.Test
 import kotlin.test.assertContentEquals
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
+import kotlin.test.assertIs
 import kotlin.test.assertNull
 import kotlin.test.assertTrue
 
@@ -91,8 +92,7 @@ class Nip88PollTagsTest {
     @Test
     fun theSpecsPollExampleParsesFieldForField() {
         val event = Event.fromJson(specPoll)
-        assertTrue(event is PollEvent)
-        val poll = event as PollEvent
+        val poll = assertIs<PollEvent>(event)
 
         assertEquals("Pineapple on pizza", poll.content)
         assertEquals(listOf("qj518h583" to "Yay", "gga6cdnqj" to "Nay"), poll.options().map { it.code to it.label })
@@ -104,8 +104,7 @@ class Nip88PollTagsTest {
     @Test
     fun theSpecsResponseExampleParsesFieldForField() {
         val event = Event.fromJson(specResponse)
-        assertTrue(event is PollResponseEvent)
-        val response = event as PollResponseEvent
+        val response = assertIs<PollResponseEvent>(event)
 
         assertEquals("1fc80cf813f1af33d5a435862b7ef7fb96b47e68a48f1abcadf8081f5a545550", response.poll()?.eventId)
         // Both tags are read. Which of them counts is the polltype's business, not the parser's.