feat: adicionar campo para criar categorias customizadas na adição/edição de projetos

frontend/src/app/admin/projetos/novo/page.tsx

@@ -30,6 +30,8 @@ export default function NewProject() {
   const coverInputRef = useRef<HTMLInputElement | null>(null);
   const galleryInputRef = useRef<HTMLInputElement | null>(null);
   const [loading, setLoading] = useState(false);
+  const [categories, setCategories] = useState(CATEGORY_OPTIONS);
+  const [newCategory, setNewCategory] = useState('');
   const [formData, setFormData] = useState({
     title: '',
     category: '',
@@ -217,10 +219,39 @@ export default function NewProject() {
                 required
               >
                 <option value="">Selecione uma categoria</option>
-                {CATEGORY_OPTIONS.map((option) => (
+                {categories.map((option) => (
                   <option key={option.value} value={option.value}>{option.label}</option>
                 ))}
               </select>
+              <p className="text-xs text-gray-500 dark:text-gray-400 mt-2">Não encontra a categoria? Adicione uma nova abaixo</p>
+            </div>
+
+            <div>
+              <label className="block text-sm font-bold text-gray-700 dark:text-gray-300 mb-2">Adicionar Nova Categoria</label>
+              <div className="flex gap-2">
+                <input 
+                  type="text" 
+                  value={newCategory}
+                  onChange={(e) => setNewCategory(e.target.value)}
+                  className="flex-1 px-4 py-3 bg-gray-50 dark:bg-white/5 border border-gray-200 dark:border-white/10 rounded-xl text-gray-900 dark:text-white focus:outline-none focus:border-primary focus:ring-1 focus:ring-primary transition-all"
+                  placeholder="Ex: Consultoria Ambiental"
+                />
+                <button
+                  type="button"
+                  onClick={() => {
+                    if (newCategory.trim()) {
+                      const newCat = { value: newCategory, label: newCategory };
+                      setCategories([...categories, newCat]);
+                      setFormData({...formData, category: newCategory});
+                      setNewCategory('');
+                      success('Categoria adicionada!');
+                    }
+                  }}
+                  className="px-4 py-3 bg-primary text-white rounded-xl font-medium hover:bg-primary/90 transition-colors whitespace-nowrap"
+                >
+                  Adicionar
+                </button>
+              </div>
             </div>
 
             <div>