Add xlsxwriter-based Excel generation scripts with openpyxl implementation

- Created create_excel_xlsxwriter.py and update_excel_xlsxwriter.py
- Uses openpyxl exclusively to preserve Excel formatting and formulas
- Updated server.js to use new xlsxwriter scripts for form submissions
- Maintains all original functionality while ensuring proper Excel file handling

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

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

venv/lib/python3.12/site-packages/openpyxl/chart/reader.py

@@ -0,0 +1,32 @@
+# Copyright (c) 2010-2024 openpyxl
+
+"""
+Read a chart
+"""
+
+def read_chart(chartspace):
+    cs = chartspace
+    plot = cs.chart.plotArea
+
+    chart = plot._charts[0]
+    chart._charts = plot._charts
+
+    chart.title = cs.chart.title
+    chart.display_blanks = cs.chart.dispBlanksAs
+    chart.visible_cells_only = cs.chart.plotVisOnly
+    chart.layout = plot.layout
+    chart.legend = cs.chart.legend
+
+    # 3d attributes
+    chart.floor = cs.chart.floor
+    chart.sideWall = cs.chart.sideWall
+    chart.backWall = cs.chart.backWall
+    chart.pivotSource = cs.pivotSource
+    chart.pivotFormats = cs.chart.pivotFmts
+    chart.idx_base = min((s.idx for s in chart.series), default=0)
+    chart._reindex()
+
+    # Border, fill, etc.
+    chart.graphical_properties = cs.graphical_properties
+
+    return chart