Add transaction parameters section to README with usage examples

Author: robocode13

README.md

@@ -215,6 +215,47 @@ For each account-specific transaction, the client provides corresponding `can*`
 | `canGetPortfolio(accountNumber?)`            | Checks if portfolio information fetching is supported           |
 | `canGetCreditCardStatements(accountNumber?)` | Checks if credit card statements fetching is supported          |
 
+### Transaction Parameters
+
+The configuration object provides methods to access transaction-specific parameters and capabilities provided by the bank:
+
+#### `config.getTransactionParameters<T>(transId: string): T | undefined`
+
+Returns the bank-specific parameters for a transaction type, if available. These parameters contain transaction limits, supported formats, and other bank-specific constraints.
+
+```typescript
+// Get parameters for account statements (MT940)
+const mt940Params = config.getTransactionParameters<HIKAZSParameter>('HKKAZ');
+
+// Get parameters for account statements (CAMT)  
+const camtParams = config.getTransactionParameters<HICAZSParameter>('HKCAZ');
+
+// Get parameters for SEPA transactions
+const sepaParams = config.getTransactionParameters<HISPASParameter>('HKSPA');
+```
+
+#### `config.isTransactionSupported(transId: string): boolean`
+
+Checks whether a specific transaction type is supported by the bank.
+
+```typescript
+if (config.isTransactionSupported('HKWPD')) {
+  console.log('Bank supports portfolio requests');
+}
+```
+
+#### `config.isAccountTransactionSupported(accountNumber: string, transId: string): boolean`
+
+Checks whether a specific transaction type is supported for a particular account.
+
+```typescript
+if (config.isAccountTransactionSupported('1234567890', 'HKWPD')) {
+  console.log('Account supports portfolio requests');
+}
+```
+
+**Note**: Transaction IDs correspond to the FinTS segment names (e.g., 'HKKAZ' for account statements, 'HKWPD' for portfolio, 'HKSAL' for balance).
+
 ### TAN Continuation Methods
 
 Every transaction that supports TAN authentication has a corresponding `*WithTan` method for continuing the transaction after TAN entry: