Add SVG combination tool and plate dimension options

Created combine_svg_vertical.py to vertically stack SVG files with centering
and configurable spacing. Enhanced svg_logo_to_stl.py with plate dimensions
and margin options for better nameplate creation.

combine_svg_vertical.py features:
- Vertically combines two SVG files (icon above text)
- Automatically centers smaller element
- Configurable spacing between elements (default: 20px)
- Configurable margin around composition (default: 10px)
- Preserves individual SVG structure in groups

svg_logo_to_stl.py enhancements:
- Added --plate-width and --plate-height options
- Logo scales to fit within plate dimensions (maintaining aspect ratio)
- Added --margin option for spacing around logo on plate
- Automatic centering of logo on plate
- Reports actual dimensions: plate, logo, margin, and offset

Example usage:
  # Combine icon and text
  python combine_svg_vertical.py um_grey.svg um_black.svg combined.svg --spacing 114

  # Center on 256x256mm plate with 10mm margin
  python svg_logo_to_stl.py combined.svg output \
    --plate-width 256 --plate-height 256 --margin 10 \
    --base-thickness 1.5 --feature-height 2.5

Files:
- combine_svg_vertical.py: Vertical SVG stacking tool
- README_combine_svg.md: Documentation for combine tool
- underground-magnetics-combined.svg: Example combined logo
- svg_logo_to_stl.py: Enhanced with plate dimensions
- command.txt: Updated with new parameters

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

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

command.txt

@@ -1,28 +1,46 @@
-# SVG to STL Conversion Command
+# SVG to Multi-Color 3D Model Converter
+# Automatically detects all colors in SVG and creates one part per color
 # Note: The DYLD_LIBRARY_PATH is needed for Cairo to work on macOS
 
+# Basic usage - specify width, logo scales proportionally
 export DYLD_LIBRARY_PATH="/opt/homebrew/lib:$DYLD_LIBRARY_PATH" && source .venv/bin/activate && python svg_logo_to_stl.py "Color logo - no background.svg" logo_output --width-mm 254 --base-thickness 1.5 --feature-height 2.5
 
+# Plate dimensions - logo scales and centers on specified plate size with margin
+python svg_logo_to_stl.py underground-magnetics-combined.svg um_logo --plate-width 256 --plate-height 256 --margin 10 --base-thickness 1.5 --feature-height 2.5
+
 # Or if you've already activated the venv and set the library path:
 python svg_logo_to_stl.py "Color logo - no background.svg" logo_output --width-mm 254 --base-thickness 1.5 --feature-height 2.5
 
+# Works with ANY SVG file! The script will:
+# 1. Automatically detect all unique colors
+# 2. Create one part per color
+# 3. Generate assembly with separate selectable parts
+
 # Output files:
-# - logo_output_base.stl - Black base plate (Z: 0 to 1.5mm)
-# - logo_output_green_icon.stl - Green microchip icon at top (Z: 1.5 to 4.0mm)
-# - logo_output_white.stl - White "SPARKSOFT DESIGN" text (Z: 1.5 to 4.0mm)
-# - logo_output_green_bottom.stl - Green "EMBEDDED SOLUTIONS" text (Z: 1.5 to 4.0mm)
-# - logo_output_assembled.stl - All parts combined (single object)
+# - logo_output_base.stl - Black base plate
+# - logo_output_{color}.stl - One STL per detected color
+# - logo_output_assembled.stl - All parts combined (single mesh)
 # - logo_output_assembled.3mf - All parts as single mesh (for paint tool)
-# - logo_output_parts.3mf - 4 separate selectable parts (BEST for multi-color!)
+# - logo_output_parts.3mf - Separate selectable parts (BEST for multi-color!)
 
 # Import logo_output_parts.3mf into BambuStudio
-# You'll see 4 separate parts that can each be assigned different filaments:
+# Each detected color becomes a separate selectable part
+# Assign different filaments to each part for multi-color printing
+
+# Example for this logo:
 #   1. base - black base plate
-#   2. green_icon - microchip icon
-#   3. white_text - middle text
-#   4. green_text - bottom text
-# Parts do NOT overlap in XY space, preventing slicing issues
-# Total model height: 4.0mm (1.5mm base + 2.5mm features)
+#   2. white - "SPARKSOFT DESIGN" text
+#   3. green - microchip icon + "EMBEDDED SOLUTIONS" text
+
+# Total model height: base_thickness + feature_height (default: 0.8mm + 1.8mm = 2.6mm)
 
 # IMPORTANT: Scale must be 254mm or larger for 0.4mm nozzle
 # Smaller sizes cause features to be too small for proper toolpath generation
+
+# Parameters:
+#   --width-mm: Logo width in mm (if plate dimensions not specified)
+#   --plate-width: Plate width in mm (logo will be scaled and centered)
+#   --plate-height: Plate height in mm (logo will be scaled and centered)
+#   --margin: Margin around logo when using plate dimensions (default: 0)
+#   --base-thickness: Base plate thickness in mm (default: 0.8)
+#   --feature-height: Raised feature height in mm (default: 1.8)