feat: Windows compatibility (#836)

* feat: win compatibility

* fix

* fix: uptime parse

* opt.: linux uptime accuracy

* fix: windows temperature fetching

* opt.

* opt.: powershell exec

* refactor: address PR review feedback and improve code quality

### Major Improvements:
- **Refactored Windows status parsing**: Broke down large `_getWindowsStatus` method into 13 smaller, focused helper methods for better maintainability and readability
- **Extracted system detection logic**: Created dedicated `SystemDetector` helper class to separate OS detection concerns from ServerProvider
- **Improved concurrency handling**: Implemented proper synchronization for server updates using Future-based locks to prevent race conditions

### Bug Fixes:
- **Fixed CPU percentage parsing**: Removed incorrect '*100' multiplication in BSD CPU parsing (values were already percentages)
- **Enhanced memory parsing**: Added validation and error handling to BSD memory fallback parsing with proper logging
- **Improved uptime parsing**: Added support for multiple Windows date formats and robust error handling with validation
- **Fixed division by zero**: Added safety checks in Swap.usedPercent getter

### Code Quality Enhancements:
- **Added comprehensive documentation**: Documented Windows CPU counter limitations and approach
- **Strengthened error handling**: Added detailed logging and validation throughout parsing methods
- **Improved robustness**: Enhanced BSD CPU parsing with percentage validation and warnings
- **Better separation of concerns**: Each parsing method now has single responsibility

### Files Changed:
- `lib/data/helper/system_detector.dart` (new): System detection helper
- `lib/data/model/server/cpu.dart`: Fixed percentage parsing and added validation
- `lib/data/model/server/memory.dart`: Enhanced fallback parsing and division-by-zero protection
- `lib/data/model/server/server_status_update_req.dart`: Refactored into 13 focused parsing methods
- `lib/data/provider/server.dart`: Improved synchronization and extracted system detection

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

* refactor: parse & shell fn struct

---------

Co-authored-by: Claude <noreply@anthropic.com>

lib/data/model/server/server_private_info.g.dart

@@ -27,6 +27,10 @@ _Spi _$SpiFromJson(Map<String, dynamic> json) => _Spi(
     (k, e) => MapEntry(k, e as String),
   ),
   id: json['id'] == null ? '' : Spi.parseId(json['id']),
+  customSystemType: $enumDecodeNullable(
+    _$SystemTypeEnumMap,
+    json['customSystemType'],
+  ),
 );
 
 Map<String, dynamic> _$SpiToJson(_Spi instance) => <String, dynamic>{
@@ -44,4 +48,12 @@ Map<String, dynamic> _$SpiToJson(_Spi instance) => <String, dynamic>{
   if (instance.wolCfg case final value?) 'wolCfg': value,
   if (instance.envs case final value?) 'envs': value,
   'id': instance.id,
+  if (_$SystemTypeEnumMap[instance.customSystemType] case final value?)
+    'customSystemType': value,
+};
+
+const _$SystemTypeEnumMap = {
+  SystemType.linux: 'linux',
+  SystemType.bsd: 'bsd',
+  SystemType.windows: 'windows',
 };