Update typespec emitter version to prerelease 1.0.0-alpha.20250419.1 (Azure#49497)

* Initialize repository for autorest build 20250419.1

* Update SDK code he_op_3

* Delete sdk/loadtestservice/Azure.Developer.LoadTesting/tests/Generated/Samples/Samples_LoadTestAdministrationClient.cs

* Delete sdk/loadtestservice/Azure.Developer.LoadTesting/tests/Generated/Samples/Samples_LoadTestRunClient.cs

---------

Co-authored-by: JoshLove-msft <[email protected]>

Author: azure-sdk

eng/http-client-csharp-emitter-package-lock.json

@@ -1,7 +1,7 @@
 {
   "main": "dist/src/index.js",
   "dependencies": {
-    "@azure-typespec/http-client-csharp": "1.0.0-alpha.20250417.3"
+    "@azure-typespec/http-client-csharp": "1.0.0-alpha.20250419.1"
   },
   "devDependencies": {
     "@azure-tools/typespec-azure-core": "0.54.0",