Fix critical Flutter SDK build errors and linting issues

- Fixed constant expression type errors by removing const from string multiplication
- Removed unused import package:flutter/services.dart from test files
- Fixed dangling library doc comments by adding library directive
- Replaced print statements with debugPrint for proper Flutter logging
- Fixed unused catch clause in error handling
- Updated constructors to use super parameters in TypeScript classes
- Fixed unused local variable in bug fixes test
- Improved const constructors and const declarations
- All critical errors and warnings resolved, only minor info-level suggestions remain

Co-authored-by: 0xrinegade <[email protected]>

Author: Copilot

flutter_sdk/example/pubspec.lock

@@ -126,18 +126,18 @@ packages:
     dependency: transitive
     description:
       name: leak_tracker
-      sha256: "7f0df31977cb2c0b88585095d168e689669a2cc9b97c309665e3386f3e9d341a"
+      sha256: "3f87a60e8c63aecc975dda1ceedbc8f24de75f09e4856ea27daf8958f2f0ce05"
       url: "https://pub.dev"
     source: hosted
-    version: "10.0.4"
+    version: "10.0.5"
   leak_tracker_flutter_testing:
     dependency: transitive
     description:
       name: leak_tracker_flutter_testing
-      sha256: "06e98f569d004c1315b991ded39924b21af84cf14cc94791b8aea337d25b57f8"
+      sha256: "932549fb305594d82d7183ecd9fa93463e9914e1b67cacc34bc40906594a1806"
       url: "https://pub.dev"
     source: hosted
-    version: "3.0.3"
+    version: "3.0.5"
   leak_tracker_testing:
     dependency: transitive
     description:
@@ -166,18 +166,18 @@ packages:
     dependency: transitive
     description:
       name: material_color_utilities
-      sha256: "0e0a020085b65b6083975e499759762399b4475f766c21668c4ecca34ea74e5a"
+      sha256: f7142bb1154231d7ea5f96bc7bde4bda2a0945d2806bb11670e30b850d56bdec
       url: "https://pub.dev"
     source: hosted
-    version: "0.8.0"
+    version: "0.11.1"
   meta:
     dependency: transitive
     description:
       name: meta
-      sha256: "7687075e408b093f36e6bbf6c91878cc0d4cd10f409506f7bc996f68220b9136"
+      sha256: bdb68674043280c3428e9ec998512fb681678676b3c54e773629ffe74419f8c7
       url: "https://pub.dev"
     source: hosted
-    version: "1.12.0"
+    version: "1.15.0"
   path:
     dependency: transitive
     description:
@@ -190,10 +190,10 @@ packages:
     dependency: transitive
     description:
       name: platform
-      sha256: "12220bb4b65720483f8fa9450b4332347737cf8213dd2840d8b2c823e47243ec"
+      sha256: "9b71283fc13df574056616011fb138fd3b793ea47cc509c189a6c3fa5f8a1a65"
       url: "https://pub.dev"
     source: hosted
-    version: "3.1.4"
+    version: "3.1.5"
   plugin_platform_interface:
     dependency: transitive
     description:
@@ -274,10 +274,10 @@ packages:
     dependency: transitive
     description:
       name: test_api
-      sha256: "9955ae474176f7ac8ee4e989dadfb411a58c30415bcfb648fa04b2b8a03afa7f"
+      sha256: "5b8a98dafc4d5c4c9c72d8b31ab2b23fc13422348d2997120294d3bac86b4ddb"
       url: "https://pub.dev"
     source: hosted
-    version: "0.7.0"
+    version: "0.7.2"
   typed_data:
     dependency: transitive
     description:
@@ -298,10 +298,10 @@ packages:
     dependency: transitive
     description:
       name: vm_service
-      sha256: "3923c89304b715fb1eb6423f017651664a03bf5f4b29983627c4da791f74a4ec"
+      sha256: "5c5f338a667b4c644744b661f309fb8080bb94b18a7e91ef1dbd343bed00ed6d"
       url: "https://pub.dev"
     source: hosted
-    version: "14.2.1"
+    version: "14.2.5"
   web:
     dependency: transitive
     description:

flutter_sdk/lib/src/network_adapters.dart

@@ -1,6 +1,7 @@
 /// Network Adapters for SVM-Pay Flutter SDK
 /// 
 /// This file implements network-specific adapters for different SVM networks.
+library;
 
 import 'types.dart';
 

flutter_sdk/lib/src/payment_widgets.dart

@@ -1,6 +1,7 @@
 /// Payment Widgets for SVM-Pay Flutter SDK
 /// 
 /// This file implements Flutter widgets for easy payment integration.
+library;
 
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';

flutter_sdk/lib/src/svm_pay_sdk.dart

@@ -1,10 +1,12 @@
 /// SVM-Pay Flutter SDK
 /// 
 /// This file implements the main SDK class for SVM-Pay Flutter integration.
+library;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:math' show Random;
+import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:crypto/crypto.dart';
 
@@ -215,7 +217,7 @@ class SVMPay {
       if (_config.debug) {
         // Fix Bug #10: More thorough error sanitization
         final sanitizedError = _sanitizeErrorMessage(e.toString());
-        print('SVM-Pay: Error parsing URL: $sanitizedError');
+        _log('Error parsing URL: $sanitizedError');
       }
       return null;
     }
@@ -265,7 +267,7 @@ class SVMPay {
           .replaceAll(RegExp(r'\b[1-9A-HJ-NP-Za-km-z]{32,44}\b'), '[ADDRESS_REDACTED]')
           .replaceAll(RegExp(r'"signature":\s*"[^"]*"'), '"signature": "[SIGNATURE_REDACTED]"')
           .replaceAll(RegExp(r'"transaction":\s*"[^"]*"'), '"transaction": "[TRANSACTION_REDACTED]"');
-      print('SVM-Pay: $sanitized');
+      debugPrint('SVM-Pay: $sanitized');
     }
   }
 
@@ -409,7 +411,7 @@ class SVMPay {
     } on PlatformException catch (e) {
       _log('Platform error getting balance: ${e.code}');
       throw Exception('Failed to get wallet balance: ${_sanitizeErrorMessage(e.message ?? 'Unknown error')}');
-    } on TimeoutException catch (e) {
+    } on TimeoutException {
       _log('Timeout getting balance');
       throw Exception('Balance request timed out. Please try again.');
     } catch (e) {

flutter_sdk/lib/src/types.dart

@@ -1,6 +1,7 @@
 /// SVM-Pay Flutter SDK Types
 /// 
 /// This file defines the core types used throughout the SVM-Pay Flutter SDK.
+library;
 
 /// Supported SVM networks
 enum SVMNetwork {
@@ -118,17 +119,14 @@ class TransferRequest extends PaymentRequest {
   const TransferRequest({
     required this.recipient,
     required this.amount,
-    required SVMNetwork network,
+    required super.network,
     this.splToken,
     this.label,
     this.message,
-    String? memo,
-    String? reference,
+    super.memo,
+    super.reference,
   }) : super(
           type: RequestType.transfer,
-          network: network,
-          memo: memo,
-          reference: reference,
         );
 
   @override
@@ -154,14 +152,11 @@ class TransactionRequest extends PaymentRequest {
 
   const TransactionRequest({
     required this.transaction,
-    required SVMNetwork network,
-    String? memo,
-    String? reference,
+    required super.network,
+    super.memo,
+    super.reference,
   }) : super(
           type: RequestType.transaction,
-          network: network,
-          memo: memo,
-          reference: reference,
         );
 
   @override

flutter_sdk/test/bug_fixes_test.dart

@@ -1,6 +1,7 @@
 /// Bug Fixes Test Suite
 /// 
 /// Comprehensive tests for critical bug fixes in the Flutter SDK.
+library;
 
 import 'package:flutter_test/flutter_test.dart';
 import 'package:svm_pay/src/svm_pay_sdk.dart';
@@ -39,13 +40,13 @@ void main() {
 
     group('Bug #2: Race Condition Prevention', () {
       test('concurrent payment requests are handled safely', () async {
-        final request1 = TransferRequest(
+        const request1 = TransferRequest(
           recipient: '11111111111111111111111111111112',
           amount: '1.0',
           network: SVMNetwork.solana,
         );
 
-        final request2 = TransferRequest(
+        const request2 = TransferRequest(
           recipient: '11111111111111111111111111111112',
           amount: '2.0',
           network: SVMNetwork.solana,
@@ -141,7 +142,7 @@ void main() {
         expect(svmPay.parseUrl(longUrl), isNull);
 
         // Test URLs with path traversal attempts
-        final maliciousUrl = 'solana://address?amount=../../../etc/passwd';
+        const maliciousUrl = 'solana://address?amount=../../../etc/passwd';
         final result = svmPay.parseUrl(maliciousUrl);
         expect(result, isNull);
 
@@ -154,7 +155,7 @@ void main() {
         expect(svmPay.parseUrl(excessiveUrl), isNull);
 
         // Test valid URL still works
-        final validUrl = 'solana://11111111111111111111111111111112?amount=1.0';
+        const validUrl = 'solana://11111111111111111111111111111112?amount=1.0';
         expect(svmPay.parseUrl(validUrl), isNotNull);
       });
     });
@@ -215,7 +216,7 @@ void main() {
            'private: [REDACTED] and token: [REDACTED]'),
         ];
 
-        for (final (input, expected) in testCases) {
+        for (final (input, _) in testCases) {
           // We need to access the private method through a test-specific approach
           // This is a simplified test - in practice, we'd test through public methods
           expect(input.contains('11111111111111111111111111111112') ||

flutter_sdk/test/integration_test.dart

@@ -1,4 +1,3 @@
-import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:integration_test/integration_test.dart';
 import 'package:svm_pay/svm_pay.dart';
@@ -352,9 +351,9 @@ void main() {
 
       testWidgets('should handle large data efficiently', (tester) async {
         // Test with maximum allowed string lengths
-        const maxLabel = 'a' * 200;
-        const maxMessage = 'b' * 500;
-        const maxMemo = 'c' * 100;
+        final maxLabel = 'a' * 200;
+        final maxMessage = 'b' * 500;
+        final maxMemo = 'c' * 100;
 
         final stopwatch = Stopwatch()..start();