Initial backup of LTP-305G matrix clock setup on matrixpi

Captures everything needed to redeploy the two-display clock (hour on I2C
0x61, minute on I2C 0x63) on a fresh Pi:

- Both systemd units (matrix0x61.service, matrix0x63.service)
- Deployed Pimoroni script tree, including the local %I (12-hour) clock
  customization
- Vendored upstream sources (ltp305-python, breakout-garden) so restore is
  fully offline-capable
- Boot config snippet enabling I2C
- install.sh that wires it all back up idempotently
- Inventory doc cross-referencing every live-system path

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

vendor/breakout-garden/examples/spirit-level/README.md

@@ -0,0 +1,46 @@
+# Spirit level example
+
+This examples emulates a circular spirit level, using the LCD to draw 
+the spirit level and the 3DoF motion sensor to detect orientation.
+
+## Pre-requisites
+
+This example requires:
+
+- A Pimoroni [Breakout Garden](https://shop.pimoroni.com/products/breakout-garden-hat-i2c-spi)
+- A Pimoroni [MSA301 3DoF Motion Sensor Breakout](https://shop.pimoroni.com/products/msa301-3dof-motion-sensor-breakout)
+- A Pimoroni [1.3" LCD Breakout](https://shop.pimoroni.com/products/1-3-spi-colour-lcd-240x240-breakout)
+
+## Installation
+
+Pop the breakouts into your Breakout Garden, and then run the `install.sh`
+script in the root of this repository with `sudo ./install.sh` to automagically
+install the libraries to run the I2C breakouts.
+
+For this example you'll need to make sure some additional software is installed:
+
+```
+sudo apt install python3-pil
+```
+
+You'll need to clone and install the library for the 1.3" LCD Breakout
+as follows:
+
+```
+git clone https://github.com/pimoroni/st7789-python
+cd library
+sudo python3 setup.py install
+```
+
+This example assumes that you have the LCD plugged into the front slot on the
+Breakout Garden HAT, which should also work with the Breakout Garden Mini HAT.
+To change it to the back slot, change `cs=ST7789.BG_SPI_CS_FRONT` to 
+`cs=ST7789.BG_SPI_CS_BACK` and `backlight=19` to backlight=18` on the line 
+where the LCD is set up. 
+
+## Running this example
+
+To run this example, type `./spirit-level.py` in the terminal.
+
+It's assumed that you have the MSA301 breakout and LCD breakout lying flat, so 
+your Raspberry Pi or Raspberry Pi Zero will be perpendicular to your flat surface.