✨ feat: Windows .bat support + settings64 env setup for Xilinx tools

Tool discovery:
- On Windows, scan .bat files in addition to .exe
  (Xilinx Windows tools use .bat wrappers, not .exe)
- Prefer .exe over .bat when both exist (same version dir)

Environment setup:
- _find_settings_script(): walk up from bin/ to find settings64.sh/.bat
- build_tool_command(): wrap Linux tool invocation with 'source settings64.sh'
  Windows .bat wrappers handle env internally, no extra wrapping needed
- reboot_manager.py now uses build_tool_command() for proper env

Example output (Linux):
  build_tool_command('/data/xilinx/Vitis/2023.2/bin/xsct', 'script.tcl')
  → ['bash', '-c', 'source .../settings64.sh && .../xsct script.tcl']

src/reboot_manager.py

@@ -231,8 +231,9 @@ exit
         if callback:
             callback("progress", "Running JTAG system reset...")
 
+        from vitis_checker import build_tool_command
         result = subprocess.run(
-            [xsct, tcl_path],
+            build_tool_command(xsct, tcl_path),
             capture_output=True,
             text=True,
             timeout=30,