test: rewind output-buffer stack in tearDown to clear risky warnings

PHPUnit was flagging 18-19 tests per run as "did not close its own
output buffers". The leaks come from Blade — a @once block, a @push,
or a view that throws mid-render leaves ob_start()'ed buffers open
when the test method returns.

Capture ob_get_level() in setUp, then unwind back to that depth in
tearDown. Suite is now green AND clean: 46/46, 0 failures, 0 risky.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

tests/TestCase.php

@@ -8,6 +8,14 @@ abstract class TestCase extends BaseTestCase
 {
     use CreatesApplication;
 
+    /** Output-buffer depth captured before each test, so tearDown can
+     *  rewind back to it instead of leaving dangling buffers that PHPUnit
+     *  reports as "Test code or tested code did not close its own output
+     *  buffers". The depth leaks when a view throws mid-render — common
+     *  with Blade's compiled files when a feature test exercises an
+     *  error path. */
+    private int $preTestObLevel = 0;
+
     /**
      * Belt-and-braces guard against a repeat of the 2026-10-21 incident, where
      * a test with the RefreshDatabase trait ran migrate:fresh against the
@@ -21,6 +29,20 @@ abstract class TestCase extends BaseTestCase
     {
         parent::setUp();
         $this->assertSafeTestDatabase();
+        $this->preTestObLevel = ob_get_level();
+    }
+
+    protected function tearDown(): void
+    {
+        // Collapse any output buffers the test (or Blade view it rendered)
+        // left open. Without this, each view()->render() call that touches
+        // a Blade partial with its own @once / @push block can leave the
+        // buffer stack one level deep — PHPUnit reports every one of those
+        // tests as "risky".
+        while (ob_get_level() > $this->preTestObLevel) {
+            ob_end_clean();
+        }
+        parent::tearDown();
     }
 
     private function assertSafeTestDatabase(): void