feat: Add company association to projects with role management

- Created Company model and migration with fields: name, tax_id, address, phone, email, website, type, notes
- Created company_project pivot table with role_in_project field
- Added relationships: Project.companies() and Company.projects()
- Created Livewire component ProjectCompanies for managing company assignments
- Added 'Companies' tab to project edit interface alongside Phases and Users tabs
- Implemented assign/remove company functionality with role selection
- Applied same permissions logic as user assignment (assign users permission or Admin role)

database/migrations/2026_05_13_075321_create_companies_table.php

@@ -0,0 +1,36 @@
+<?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
+    {
+        Schema::create('companies', function (Blueprint $table) {
+            $table->id();
+            $table->string('name');
+            $table->string('tax_id')->nullable()->unique();
+            $table->string('address')->nullable();
+            $table->string('phone')->nullable();
+            $table->string('email')->nullable();
+            $table->string('website')->nullable();
+            $table->enum('type', ['owner', 'constructor', 'subcontractor', 'consultant', 'supplier', 'other'])->default('other');
+            $table->text('notes')->nullable();
+            $table->timestamps();
+            $table->softDeletes();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('companies');
+    }
+};