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/core/extension/sftpfile.dart

@@ -12,21 +12,9 @@ extension SftpFileX on SftpFileMode {
 
   UnixPerm toUnixPerm() {
     return UnixPerm(
-      user: UnixPermOp(
-        r: userRead,
-        w: userWrite,
-        x: userExecute,
-      ),
-      group: UnixPermOp(
-        r: groupRead,
-        w: groupWrite,
-        x: groupExecute,
-      ),
-      other: UnixPermOp(
-        r: otherRead,
-        w: otherWrite,
-        x: otherExecute,
-      ),
+      user: UnixPermOp(r: userRead, w: userWrite, x: userExecute),
+      group: UnixPermOp(r: groupRead, w: groupWrite, x: groupExecute),
+      other: UnixPermOp(r: otherRead, w: otherWrite, x: otherExecute),
     );
   }
 }

lib/core/extension/ssh_client.dart

@@ -4,6 +4,7 @@ import 'dart:typed_data';
 import 'package:dartssh2/dartssh2.dart';
 import 'package:fl_lib/fl_lib.dart';
 import 'package:flutter/widgets.dart';
+import 'package:server_box/data/model/server/system.dart';
 
 import 'package:server_box/data/res/misc.dart';
 
@@ -13,6 +14,52 @@ typedef OnStdin = void Function(SSHSession session);
 typedef PwdRequestFunc = Future<String?> Function(String? user);
 
 extension SSHClientX on SSHClient {
+  /// Create a persistent PowerShell session for Windows commands
+  Future<(SSHSession, String)> execPowerShell(
+    OnStdin onStdin, {
+    SSHPtyConfig? pty,
+    OnStdout? onStdout,
+    OnStdout? onStderr,
+    bool stdout = true,
+    bool stderr = true,
+    Map<String, String>? env,
+  }) async {
+    final session = await execute(
+      'powershell -NoLogo -NoProfile -NonInteractive -ExecutionPolicy Bypass',
+      pty: pty,
+      environment: env,
+    );
+
+    final result = BytesBuilder(copy: false);
+    final stdoutDone = Completer<void>();
+    final stderrDone = Completer<void>();
+
+    session.stdout.listen(
+      (e) {
+        onStdout?.call(e.string, session);
+        if (stdout) result.add(e);
+      },
+      onDone: stdoutDone.complete,
+      onError: stderrDone.completeError,
+    );
+
+    session.stderr.listen(
+      (e) {
+        onStderr?.call(e.string, session);
+        if (stderr) result.add(e);
+      },
+      onDone: stderrDone.complete,
+      onError: stderrDone.completeError,
+    );
+
+    onStdin(session);
+
+    await stdoutDone.future;
+    await stderrDone.future;
+
+    return (session, result.takeBytes().string);
+  }
+
   Future<(SSHSession, String)> exec(
     OnStdin onStdin, {
     String? entry,
@@ -22,9 +69,14 @@ extension SSHClientX on SSHClient {
     bool stdout = true,
     bool stderr = true,
     Map<String, String>? env,
+    SystemType? systemType,
   }) async {
     final session = await execute(
-      entry ?? 'cat | sh',
+      entry ??
+          switch (systemType) {
+            SystemType.windows => 'powershell -NoLogo -NoProfile -NonInteractive -ExecutionPolicy Bypass',
+            _ => 'cat | sh',
+          },
       pty: pty,
       environment: env,
     );
@@ -81,9 +133,7 @@ extension SSHClientX on SSHClient {
           isRequestingPwd = true;
           final user = Miscs.pwdRequestWithUserReg.firstMatch(data)?.group(1);
           if (context == null) return;
-          final pwd = context.mounted
-              ? await context.showPwdDialog(title: user, id: id)
-              : null;
+          final pwd = context.mounted ? await context.showPwdDialog(title: user, id: id) : null;
           if (pwd == null || pwd.isEmpty) {
             session.stdin.close();
           } else {