feat: Refactor transaction management with nanostores and convert components to React

- Added @nanostores/react for state management.
- Created AccountSummary component to display account balance.
- Replaced AddTransactionForm.astro with AddTransactionForm.tsx for better state handling.
- Introduced TransactionTable.tsx for displaying transactions with edit/delete functionality.
- Updated Sidebar.astro and MainContent.astro to use React components.
- Implemented transactionStore.ts for managing current account ID and transaction editing state.
- Removed obsolete AddTransactionForm.astro and related scripts.
- Enhanced error handling and loading states in transaction forms.
This fixes issues #7, #8, #9, #10, #11

src/components/MainContent.astro

@@ -1,18 +1,16 @@
 ---
-import TransactionTable from './TransactionTable.astro';
-import type { Account, Transaction } from '../types';
+import TransactionTable from './TransactionTable.tsx';
+import type { Account } from '../types';
 
 interface Props {
     account: Account;
-    transactions: Transaction[];
 }
 
-const { account, transactions } = Astro.props;
+const { account } = Astro.props;
 ---
 <main class="main-content">
     <header class="main-header">
          <h1>Transactions for <span id="current-account-name">{account.name} (***{account.last4})</span></h1>
     </header>
-    /* Make table updatable */
-    <TransactionTable transactions={transactions} client:load /> {}
+    <TransactionTable client:load />
 </main>