Update Web UI: Add server management scripts and improve UX

UI improvements:
- Add icon-based Execute/Edit/Delete buttons for scripts and callbacks
- Add execution result dialog with stdout/stderr and execution time
- Add favicon with media player icon
- Disable background scrolling when dialogs are open
- Add footer with author information and source code link

Backend enhancements:
- Add execution time tracking to script and callback execution
- Add /api/callbacks/execute endpoint for debugging callbacks
- Return detailed execution results (stdout, stderr, exit_code, execution_time)

Server management:
- Add scripts/start-server.bat - Start server with console window
- Add scripts/start-server-background.vbs - Start server silently
- Add scripts/stop-server.bat - Stop running server instances
- Add scripts/restart-server.bat - Restart the server

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

scripts/restart-server.bat

@@ -0,0 +1,24 @@
+@echo off
+REM Media Server Restart Script
+REM This script restarts the media server
+
+echo Restarting Media Server...
+echo.
+
+REM Stop the server first
+echo [1/2] Stopping server...
+call "%~dp0\stop-server.bat"
+
+REM Wait a moment
+timeout /t 2 /nobreak >nul
+
+REM Change to parent directory (media-server root)
+cd /d "%~dp0\.."
+
+REM Start the server
+echo.
+echo [2/2] Starting server...
+python -m media_server.main
+
+REM If the server exits, pause to show any error messages
+pause

scripts/start-server-background.vbs

@@ -0,0 +1,7 @@
+Set WshShell = CreateObject("WScript.Shell")
+Set FSO = CreateObject("Scripting.FileSystemObject")
+' Get parent folder of scripts folder (media-server root)
+WshShell.CurrentDirectory = FSO.GetParentFolderName(FSO.GetParentFolderName(WScript.ScriptFullName))
+WshShell.Run "python -m media_server.main", 0, False
+Set FSO = Nothing
+Set WshShell = Nothing

scripts/start-server.bat

@@ -0,0 +1,15 @@
+@echo off
+REM Media Server Startup Script
+REM This script starts the media server
+
+echo Starting Media Server...
+echo.
+
+REM Change to the media-server directory (parent of scripts folder)
+cd /d "%~dp0\.."
+
+REM Start the media server
+python -m media_server.main
+
+REM If the server exits, pause to show any error messages
+pause

scripts/stop-server.bat

@@ -0,0 +1,19 @@
+@echo off
+REM Media Server Stop Script
+REM This script stops the running media server
+
+echo Stopping Media Server...
+echo.
+
+REM Find and kill Python processes running media_server.main
+for /f "tokens=2" %%i in ('tasklist /FI "IMAGENAME eq python.exe" /FO LIST ^| findstr /B "PID:"') do (
+    wmic process where "ProcessId=%%i" get CommandLine 2>nul | findstr /C:"media_server.main" >nul
+    if not errorlevel 1 (
+        taskkill /PID %%i /F
+        echo Media server process (PID %%i) terminated.
+    )
+)
+
+echo.
+echo Done! Media server stopped.
+pause