WIP: ARGB implementation.

Start of ARGB code.

Add mermaid diagram for i2c.

Make access to internal_tick in timer atomic.

Remove modulo from time tracking, computationally expensive.

Remove legacy debug, improve timer ticks, prevent bootloader jumping to invalid application.

Make spi_transaction_t not mutated, add guards.

Harden up FSM implementation.

Fix up I2C to protect against edge conditions.

Tidy up Edgework, add serial label and font to Common.

Update some files to KiCad 10.

Test I2C in edgework.

Add I2C to backplane.

Increase chase to 16 bits.

Update SPI state names to remove clashes, ensure pins are only configured if present.