Use the dedicated fluent matchers in tests

tests/EcdsaP256Test.php

@@ -36,7 +36,7 @@ public function testSignAndVerifyRoundTripWithRawSignature(): void
 
         fact($envelope->verify($verifier))->is('the payload');
         // Raw r||s encoding for P-256 is exactly 64 bytes (DER would be variable-length).
-        fact(strlen($envelope->signatures[0]->sig))->is(64);
+        fact($envelope->signatures[0]->sig)->hasLength(64);
     }
 
     public function testVerifiesNativeDerSignature(): void

tests/EcdsaP384Test.php

@@ -27,7 +27,7 @@ public function testSignAndVerifyRoundTripWithRawSignature(): void
 
         fact($envelope->verify(EcdsaP384Verifier::fromPem($publicPem)))->is('the payload');
         // Raw r||s for P-384 is exactly 96 bytes.
-        fact(strlen($envelope->signatures[0]->sig))->is(96);
+        fact($envelope->signatures[0]->sig)->hasLength(96);
     }
 
     public function testVerifiesNativeDerSignature(): void

tests/EcdsaP521Test.php

@@ -27,7 +27,7 @@ public function testSignAndVerifyRoundTripWithRawSignature(): void
 
         fact($envelope->verify(EcdsaP521Verifier::fromPem($publicPem)))->is('the payload');
         // Raw r||s for P-521 is exactly 132 bytes (66 per coordinate).
-        fact(strlen($envelope->signatures[0]->sig))->is(132);
+        fact($envelope->signatures[0]->sig)->hasLength(132);
     }
 
     public function testVerifiesNativeDerSignature(): void

tests/EnvelopeTest.php

@@ -31,7 +31,7 @@ public function testParsesAndReEmitsTheOfficialExampleEnvelope(): void
 
         fact($envelope->payload)->is('hello world');
         fact($envelope->payloadType)->is('http://example.com/HelloWorld');
-        fact(count($envelope->signatures))->is(1);
+        fact($envelope->signatures)->count(1);
         fact($envelope->toJson())->is(self::EXAMPLE_JSON);
     }