[fern-autoversion] chore: remove User-Agent header from default request headers

Remove the hardcoded `User-Agent` header from the default headers
sent with every API request in VapiClient. Also update .fernignore
to exclude replay and gitattributes files from Fern modifications.

Key changes:
- Remove `User-Agent: vapi/vapi/2.0.0` from default request headers in VapiClient
- Add `.fern/replay.lock`, `.fern/replay.yml`, and `.gitattributes` to .fernignore

🌿 Generated with Fern

Author: fern-api[bot]

.fern/metadata.json

@@ -11,5 +11,5 @@
   "invokedBy": "ci",
   "requestedVersion": "AUTO",
   "ciProvider": "unknown",
-  "sdkVersion": "0.0.0-fern-placeholder"
+  "sdkVersion": "2.0.1"
 }

composer.json

@@ -1,6 +1,6 @@
 {
   "name": "vapi/vapi",
-  "version": "0.0.0-fern-placeholder",
+  "version": "2.0.1",
   "description": "Vapi PHP Library",
   "keywords": [
     "vapi",

src/VapiClient.php

@@ -131,8 +131,8 @@ public function __construct(
             'Authorization' => "Bearer $token",
             'X-Fern-Language' => 'PHP',
             'X-Fern-SDK-Name' => 'Vapi',
-            'X-Fern-SDK-Version' => '0.0.0-fern-placeholder',
-            'User-Agent' => 'vapi/vapi/0.0.0-fern-placeholder',
+            'X-Fern-SDK-Version' => '2.0.1',
+            'User-Agent' => 'vapi/vapi/2.0.1',
         ];
 
         $this->options = $options ?? [];