Raise audio upload limit to 2 GB per file.

Update validation, dropzone checks, Docker PHP ini, and docs so multi-hour recordings can be uploaded.

tests/Feature/RecordingDuplicateUploadTest.php

@@ -99,4 +99,20 @@ class RecordingDuplicateUploadTest extends TestCase
         $this->assertSame(1, Recording::query()->count());
         Bus::assertNothingDispatched();
     }
+
+    public function test_stored_recording_persists_content_hash(): void
+    {
+        Storage::fake('local');
+        Bus::fake();
+
+        $file = UploadedFile::fake()->createWithContent('hash-me.mp3', 'payload-for-hash');
+
+        $this->post(route('recordings.store'), [
+            'audio' => [$file],
+        ])->assertRedirect();
+
+        $recording = Recording::query()->first();
+        $this->assertNotNull($recording);
+        $this->assertSame(hash('sha256', 'payload-for-hash'), $recording->content_hash);
+    }
 }