Update: Add EUR currency support for Slovak companies

- Modified get_cz_qr_code_base64() to support both CZK and EUR
- Updated cz_to_iban() to better handle international IBANs (SK, etc.)
- SPAYD QR now uses actual invoice currency in CC: field
- Updated manifest description to reflect EUR support
- Updated README with setup instructions for Slovak companies

This allows Slovak companies with EUR accounts to generate SPAYD QR codes
for Czech customers, enabling cross-border EUR payments via mobile banking.

Generated by Mistral Vibe.
Co-Authored-By: Mistral Vibe <vibe@mistral.ai>

models/account_move.py

@@ -9,10 +9,14 @@ class AccountMove(models.Model):
     def get_cz_qr_code_base64(self):
         """ Returns Base64 PNG image for the invoice PDF """
         self.ensure_one()
-        if self.currency_id.name != 'CZK':
+        
+        # Support both EUR and CZK currencies
+        # (for Slovak companies invoicing Czech customers in EUR)
+        allowed_currencies = ['CZK', 'EUR']
+        if self.currency_id.name not in allowed_currencies:
             return False
 
-        # Find bank: 1. Matching CZK, 2. No currency set (default)
+        # Find bank: 1. Matching currency, 2. No currency set (default)
         bank = self.company_id.partner_id.bank_ids.filtered(lambda b: b.currency_id == self.currency_id)[:1]
         if not bank:
             bank = self.company_id.partner_id.bank_ids.filtered(lambda b: not b.currency_id)[:1]
@@ -21,11 +25,13 @@ class AccountMove(models.Model):
             return False
 
         # Build SPAYD string
+        # Note: cz_to_iban handles both CZ format (123-456/0800) and IBAN format (SK..., CZ..., etc.)
         iban = self.cz_to_iban(bank.acc_number)
         amount = '%.2f' % self.amount_residual
         vs = ''.join(filter(str.isdigit, self.payment_reference or ''))[-10:]
+        currency = self.currency_id.name or 'EUR'
         
-        spayd = f"SPD*1.0*ACC:{iban}*AM:{amount}*CC:CZK*X-VS:{vs}"
+        spayd = f"SPD*1.0*ACC:{iban}*AM:{amount}*CC:{currency}*X-VS:{vs}"
 
         # Generate QR Image
         qr = qrcode.make(spayd)
@@ -35,23 +41,31 @@ class AccountMove(models.Model):
 
     def cz_to_iban(self, acc_number):
         """
-        Converts '123-456/0800' or '456/0800' to a valid CZ IBAN.
+        Converts Czech account number formats to IBAN.
+        
+        Supports:
+        - Czech local format: '123-456/0800' or '456/0800'
+        - IBAN format: 'CZ6508000000001234567890', 'SK6509000000005123456789', etc.
+        
+        Returns:
+            str: Valid IBAN (uppercase) or original input if conversion fails
         """
         if not acc_number:
             return ""
         
         # Clean the input
-        clean_acc = acc_number.replace(" ", "")
+        clean_acc = acc_number.replace(" ", "").upper()
         
-        # If already an IBAN, return it
-        if clean_acc.upper().startswith('CZ'):
-            return clean_acc.upper()
+        # If already an IBAN (any country), return it
+        # IBAN format: 2-letter country code + 2-digit checksum + account number
+        if len(clean_acc) >= 4 and clean_acc[:2].isalpha() and clean_acc[2:4].isdigit():
+            return clean_acc
     
         try:
             # Split into [prefix-main, bank_code]
             parts = clean_acc.split('/')
             if len(parts) != 2:
-                return clean_acc # Fallback
+                return clean_acc  # Fallback for non-CZ format
                 
             bank_code = parts[1]
             account_parts = parts[0].split('-')