ci(android): print full assertion messages for failing tests

CI run 3161 reported seven failures as bare "java.lang.AssertionError at
UpdateVeilControllerTest.kt:87" — and line 87 is the test's own `fun ... =
runTest {` line, not the assertion. Gradle picks the first stack frame
belonging to the test class, and assertions inside a `runTest { }` lambda
live in a generated suspend-lambda class that gets filtered out, so every
failure in a coroutine test collapses to the function declaration. With the
HTML report unreachable from CI, that leaves nothing to debug from.

testLogging with exceptionFormat = FULL prints the assertion message and the
whole stack trace for failures, which is what makes a coroutine-test failure
diagnosable at all here.

Also drop the NonCancellable floor-join from UpdateVeilController's finally.
Honouring the minimum hold while the scope is being torn down is pointless —
nothing is left to render the veil — and a finally that suspends is a finally
that can resist cancellation. The floor is now awaited in the try instead.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

android/app/build.gradle.kts

@@ -210,4 +210,17 @@ dependencies {
     debugImplementation(libs.compose.ui.test.manifest)
 }
 
-tasks.withType<Test> { useJUnitPlatform() }
+tasks.withType<Test> {
+    useJUnitPlatform()
+    // Print the assertion message + full stack trace for failures. The
+    // default console output gives only "AssertionError at Foo.kt:12", and
+    // for a failure inside a `runTest { }` lambda even that line collapses
+    // to the test function's own line (the assertion frames live in the
+    // suspend-lambda class, which Gradle filters out) — leaving nothing to
+    // debug from when the HTML report isn't reachable, as in CI.
+    testLogging {
+        events("failed")
+        exceptionFormat = org.gradle.api.tasks.testing.logging.TestExceptionFormat.FULL
+        showStackTraces = true
+    }
+}

android/app/src/main/java/com/fabledsword/minstrel/shared/UpdateVeilController.kt

@@ -3,7 +3,6 @@ package com.fabledsword.minstrel.shared
 import kotlinx.coroutines.CompletableDeferred
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.FlowPreview
-import kotlinx.coroutines.NonCancellable
 import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.Flow
@@ -14,7 +13,6 @@ import kotlinx.coroutines.flow.debounce
 import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
-import kotlinx.coroutines.withContext
 import kotlinx.coroutines.withTimeoutOrNull
 
 // Once raised, the veil stays up at least this long. Without a floor a
@@ -166,15 +164,15 @@ class UpdateVeilController(
             // here before the raiser has been dispatched, tear the session
             // down, and leave the churn uncovered.
             withTimeoutOrNull(timings.maxHoldMs) { awaitSettled() }
+            // Honour the no-flash minimum before lowering. Deliberately in
+            // the try and not the finally: on cancellation the scope is
+            // going away and nothing will render the veil, so the floor is
+            // pointless there — and a finally that suspends is a finally
+            // that can resist teardown.
+            if (raised.isCompleted) floor.join()
         } finally {
             raiser.cancel()
             ceiling.cancel()
-            if (raised.isCompleted) {
-                // NonCancellable so the floor is honoured (and the veil
-                // always cleared) even while the scope is torn down; the
-                // floor job dies with the scope, so this cannot hang.
-                withContext(NonCancellable) { floor.join() }
-            }
             floor.cancel()
             visibleInternal.value = false
         }