fix(cv-search-data): use MigrationConstants.SchemaName in AddJobProviders migration

Replace hardcoded "cvSearch" string literals with MigrationConstants.SchemaName
in the Up, InsertData, and Down methods, consistent with all other migrations.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Apis/cv-search-data/Migrations/20260529084440_AddJobProviders.cs

@@ -12,7 +12,7 @@ namespace CvSearch.Data.Migrations
         {
             migrationBuilder.CreateTable(
                 name: "JobProviders",
-                schema: "cvSearch",
+                schema: MigrationConstants.SchemaName,
                 columns: table => new
                 {
                     Id = table.Column<int>(type: "int", nullable: false)
@@ -33,7 +33,7 @@ namespace CvSearch.Data.Migrations
             // Seed the three default providers — all disabled so the feature is opt-in per environment.
             // Enable a provider by setting its Enabled column to 1 via SQL or a future admin UI.
             migrationBuilder.InsertData(
-                schema: "cvSearch",
+                schema: MigrationConstants.SchemaName,
                 table: "JobProviders",
                 columns: ["Name", "Enabled", "SearchUrlTemplate", "JobLinkContains", "InitialKeywordsJson", "MaxResults", "DisplayOrder"],
                 values: new object[,]
@@ -49,7 +49,7 @@ namespace CvSearch.Data.Migrations
         {
             migrationBuilder.DropTable(
                 name: "JobProviders",
-                schema: "cvSearch");
+                schema: MigrationConstants.SchemaName);
         }
     }
 }