feat: add financial transactions management for companies

- Implemented a new route for managing financial transactions (money) for companies, including creating, editing, and deleting transactions.
- Added a new model `Buchung` to represent transactions with fields for date, account type, transaction type, amount, and description.
- Updated the `companies` model to include a relation to the new `Buchung` model.
- Enhanced the company overview page to link to the new financial transactions page.
- Added migration scripts to create the necessary database tables and fields for the new functionality.
- Created utility scripts for resetting the admin password and setting up the initial admin user.

prisma/migrations/20260324162325_add_zahlungsart_steuersatz/migration.sql

@@ -0,0 +1,7 @@
+-- AlterTable
+ALTER TABLE `betriebsausgaben` ADD COLUMN `steuersatz` DECIMAL(5, 2) NOT NULL DEFAULT 0,
+    ADD COLUMN `zahlungsart` ENUM('KASSE', 'BANK') NOT NULL DEFAULT 'BANK';
+
+-- AlterTable
+ALTER TABLE `betriebseinnahmen` ADD COLUMN `steuersatz` DECIMAL(5, 2) NOT NULL DEFAULT 0,
+    ADD COLUMN `zahlungsart` ENUM('KASSE', 'BANK') NOT NULL DEFAULT 'BANK';

prisma/migrations/20260324172641_add_money_field/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE `companies` ADD COLUMN `money` JSON NULL;

prisma/migrations/20260324175608_add_buchungen_model/migration.sql

@@ -0,0 +1,28 @@
+/*
+  Warnings:
+
+  - You are about to drop the column `money` on the `companies` table. All the data in the column will be lost.
+
+*/
+-- AlterTable
+ALTER TABLE `companies` DROP COLUMN `money`;
+
+-- CreateTable
+CREATE TABLE `buchungen` (
+    `id` VARCHAR(191) NOT NULL,
+    `companyId` VARCHAR(191) NOT NULL,
+    `date` DATETIME(3) NOT NULL,
+    `account` ENUM('KASSE', 'BANK') NOT NULL,
+    `type` ENUM('EINLAGE', 'ENTNAHME') NOT NULL,
+    `amount` DECIMAL(10, 2) NOT NULL,
+    `description` TEXT NULL,
+    `createdAt` DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
+    `updatedAt` DATETIME(3) NOT NULL,
+
+    INDEX `buchungen_companyId_idx`(`companyId`),
+    INDEX `buchungen_date_idx`(`date`),
+    PRIMARY KEY (`id`)
+) DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+
+-- AddForeignKey
+ALTER TABLE `buchungen` ADD CONSTRAINT `buchungen_companyId_fkey` FOREIGN KEY (`companyId`) REFERENCES `companies`(`id`) ON DELETE CASCADE ON UPDATE CASCADE;