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/ltp305-python/library/README.md

@@ -0,0 +1,33 @@
+# LTP305 - Breakout Garden dual 5x7 LED matrix driver
+
+[![Build Status](https://travis-ci.com/pimoroni/ltp305-python.svg?branch=master)](https://travis-ci.com/pimoroni/ltp305-python)
+[![Coverage Status](https://coveralls.io/repos/github/pimoroni/ltp305-python/badge.svg?branch=master)](https://coveralls.io/github/pimoroni/ltp305-python?branch=master)
+[![PyPi Package](https://img.shields.io/pypi/v/ltp305.svg)](https://pypi.python.org/pypi/ltp305)
+[![Python Versions](https://img.shields.io/pypi/pyversions/ltp305.svg)](https://pypi.python.org/pypi/ltp305)
+
+# Pre-requisites
+
+You must enable i2c:
+
+* i2c: `sudo raspi-config nonint do_i2c 0`
+
+You can optionally run `sudo raspi-config` or the graphical Raspberry Pi Configuration UI to enable interfaces.
+
+# Installing
+
+Stable library from PyPi:
+
+* Just run `sudo pip3 install ltp305`
+
+Latest/development library from GitHub:
+
+* `git clone https://github.com/pimoroni/ltp305-python`
+* `cd ltp305-python`
+* `sudo ./install.sh`
+
+
+# Changelog
+0.0.1
+-----
+
+* Initial Release