feat(blender): implement advanced blender features and fixes

This commit addresses several issues and implements new features for the Seed Blender based on user feedback.

- **Flexible QR Scanning**: `QRScanner` is now content-agnostic. `SeedBlender` detects QR content type (Plain Text, Krux, SeedPGP) and triggers the appropriate workflow.
- **Per-Row Decryption**: Replaces the global security panel with a per-row password input for encrypted mnemonics, allowing multiple different encrypted seeds to be used.
- **Data Loss Warning**: Implements a confirmation dialog that warns the user if they try to switch tabs with unsaved data in the blender, preventing accidental data loss.
- **Final Mnemonic Actions**: Adds 'Transfer to Backup' and 'Export as QR' buttons to the final mnemonic display, allowing the user to utilize the generated seed.
- **Refactors `SeedBlender` state management** around a `MnemonicEntry` interface for robustness and clarity.

src/components/QRScanner.tsx

@@ -40,12 +40,11 @@ export default function QRScanner({ onScanSuccess, onClose }: QRScannerProps) {
                     aspectRatio: 1.0,
                 },
                 (decodedText) => {
-                    if (decodedText.startsWith('SEEDPGP1:')) {
+                    // Stop scanning after the first successful detection
+                    if (decodedText) {
                         setSuccess(true);
                         onScanSuccess(decodedText);
                         stopCamera();
-                    } else {
-                        setError('QR code found, but not a valid SEEDPGP1 frame');
                     }
                 },
                 () => {
@@ -89,13 +88,9 @@ export default function QRScanner({ onScanSuccess, onClose }: QRScannerProps) {
             // Try scanning with verbose mode
             const decodedText = await html5QrCode.scanFile(file, true);
 
-            if (decodedText.startsWith('SEEDPGP1:')) {
-                setSuccess(true);
-                onScanSuccess(decodedText);
-                html5QrCode.clear();
-            } else {
-                setError(`Found QR code, but not SEEDPGP format: ${decodedText.substring(0, 30)}...`);
-            }
+            setSuccess(true);
+            onScanSuccess(decodedText);
+            html5QrCode.clear();
         } catch (err: any) {
             console.error('File scan error:', err);