Summary

Adds 3D rendering for PCB component bodies and SMT pads that were previously missing from the STEP output.

Changes

• Render pcb_component elements as 3D rectangular blocks with 1.5mm height for better visibility
• Render pcb_smtpad rectangular pads as 3D blocks with 0.035mm thickness (standard SMT pad thickness)
• Position all components on top of the PCB board surface at correct Z-coordinates
• Increase solid count from 2 to 26 (1 board + 4 component bodies + 20+ SMT pads)
• Add visual regression test with snapshot for repro01
• Increase test timeout to 60s for snapshot generation

Visual Results

Before: Missing resistor blocks indicated by arrows in issue #6

After:

Resistor component bodies and SMT pads are now clearly visible on the PCB surface.

Test Results

• All 6 tests pass
• Solids created increased from 2 to 26
• Visual snapshots updated for basics04 and repro01

/claim #6 I request the maintainers to please review my PR @seveibar @imrishabh18