Refine repository structure for KiCad 9 optimization

- Add dedicated /kicad/ directory with organized subdirectories for libraries, schematics, gerbers, plots, and backups
- Create comprehensive KiCad 9 library structure (symbols, footprints, 3D models)
- Add manufacturing-ready directories for production files (gerbers, drill, pick-and-place)
- Update all README files with KiCad-specific documentation and workflows
- Add KiCad-optimized .gitignore file for proper version control
- Create KICAD-PROJECT-TEMPLATE.md comprehensive usage guide
- Add hardware assembly documentation and BOM management
- Include detailed manufacturing file generation instructions
- Add docs structure with design-notes and user-manual directories
- Provide complete workflow from design to manufacturing with quality checklists

hardware/assembly/README.md

@@ -0,0 +1,81 @@
+# /hardware/assembly
+
+Assembly drawings and instructions for your KiCad project.
+
+## Purpose
+This directory contains assembly-related documentation and drawings that help with the physical construction of your PCB:
+- Assembly drawings
+- Component placement guides
+- Assembly instructions
+- Pick and place references
+
+## File Types
+- **`.pdf`**: Assembly drawings and instructions
+- **`.png/.jpg`**: Assembly photos and diagrams
+- **`.txt/.md`**: Text-based assembly instructions
+- **`.csv`**: Component placement data
+
+## Assembly Drawings from KiCad
+1. Open your PCB (`.kicad_pcb`)
+2. Go to **File → Plot**
+3. Select layers for assembly:
+   - F.Fab (Front Fabrication)
+   - B.Fab (Back Fabrication)
+   - F.SilkS (Front Silkscreen)
+   - B.SilkS (Back Silkscreen)
+4. Enable "Plot footprint values" and "Plot reference designators"
+5. Set output directory and plot
+
+## Recommended Assembly Files
+```
+assembly/
+├── ProjectName-Assembly-Top.pdf      # Top side assembly drawing
+├── ProjectName-Assembly-Bottom.pdf   # Bottom side assembly drawing
+├── ProjectName-Assembly-Guide.pdf    # Complete assembly instructions
+├── ProjectName-Placement.csv         # Component placement coordinates
+├── assembly-photos/
+│   ├── step1-power-components.jpg
+│   ├── step2-mcu-section.jpg
+│   └── step3-connectors.jpg
+└── instructions/
+    ├── assembly-checklist.md
+    ├── soldering-notes.md
+    └── testing-procedure.md
+```
+
+## Assembly Drawing Guidelines
+- Include component reference designators
+- Show component values where helpful
+- Indicate polarity for polarized components
+- Mark pin 1 locations for ICs
+- Include assembly notes and warnings
+- Use different colors for different component types
+
+## Assembly Instructions Content
+- **Component list**: What components go where
+- **Assembly order**: Sequence for efficient assembly
+- **Special procedures**: Unique assembly steps
+- **Soldering notes**: Temperature, time, flux requirements
+- **Testing points**: Where to probe during assembly
+- **Troubleshooting**: Common issues and solutions
+
+## Pick and Place Data
+Generate component placement data for automated assembly:
+1. In KiCad PCB editor, go to **File → Fabrication Outputs → Component Placement**
+2. Configure format (CSV recommended)
+3. Include position, rotation, and side information
+4. Save to this directory
+
+## Quality Control
+- **Assembly checklist**: Step-by-step verification
+- **Visual inspection**: What to look for
+- **Electrical testing**: Basic functionality tests
+- **Rework procedures**: How to fix common mistakes
+
+## Best Practices
+- Create assembly drawings at 1:1 scale when possible
+- Use clear, high-contrast colors
+- Include revision information
+- Document any special tools required
+- Provide multiple views for complex assemblies
+- Include photos of completed assembly