Fix broken Claude Code documentation links

Update all references from docs.anthropic.com/en/docs/claude-code
to code.claude.com/docs after documentation site migration.

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

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

scripts/setup.bat

@@ -35,7 +35,7 @@ if %errorlevel%==0 (
     echo [OK] Claude Code is installed
 ) else (
     echo [WARNING] Claude Code CLI not found
-    echo Install from: https://docs.anthropic.com/en/docs/claude-code
+    echo Install from: https://code.claude.com/docs
     set /p CONTINUE="Continue without Claude Code? (y/n): "
     if /i not "!CONTINUE!"=="y" exit /b 1
 )