feat: add multi-theme docker compose configuration and batch packaging scripts

docs/docker/build-and-export-player-main.bat

@@ -0,0 +1,30 @@
+@echo off
+REM Build and export main player theme only.
+REM Automatically switches to 'main' branch, builds, and restores original branch.
+REM Usage: docs\docker\build-and-export-player-main.bat [options]
+
+cd /d "%~dp0..\.."
+set "BRANCH=main"
+set "TAG=main"
+
+set "ORIGINAL_BRANCH="
+for /f "delims=" %%B in ('git rev-parse --abbrev-ref HEAD 2^>nul') do set "ORIGINAL_BRANCH=%%B"
+if not defined ORIGINAL_BRANCH (
+  echo ERROR: Cannot determine current Git branch.
+  exit /b 1
+)
+
+echo [INFO] Switching to branch %BRANCH%...
+git checkout %BRANCH% >nul 2>&1
+if errorlevel 1 (
+  echo [ERROR] Cannot switch to branch %BRANCH%
+  exit /b 1
+)
+
+call docs\docker\build-and-export-images.bat --service player --tag %TAG% %*
+set "BUILD_STATUS=%ERRORLEVEL%"
+
+echo [INFO] Restoring original branch: %ORIGINAL_BRANCH%
+git checkout %ORIGINAL_BRANCH% >nul 2>&1
+
+exit /b %BUILD_STATUS%