Add unique constraint to project name (#2099)

Project name uniqueness is currently defined implicitly via the controls
we provide to create projects. This PR adds a unique constraint to the
project name column to ensure that it is impossible for projects with
duplicate names to be created.

database/migrations/2024_03_22_031040_project_unique_name.php

@@ -0,0 +1,33 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration {
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        // Add the unique constraint.
+        // Note: This migration will fail if two projects with the same name exist in the database.
+        //       Since having two projects with the same name is undefined behavior, and should
+        //       never happen in theory, we defer to the CDash administrator to decide what to do.
+        //       The CDash UI prevents duplicate projects from being created, so this should never
+        //       occur under normal circumstances.
+        Schema::table('project', function (Blueprint $table) {
+            $table->unique('name');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('project', function (Blueprint $table) {
+            $table->dropUnique(['name']);
+        });
+    }
+};