Contributor sign-offs: https://git.card10.badge.events.ccc.de/badge23/firmware/-/issues/5

This is an annoyingly large change, but the gist of it is that we:

1. Move ctx into components/ctx
2. Move uctx into usermodule/mp_uctx.c
3. Split out uctx config into ctx_config.h and share it with the
   simulator.
4. Delete a bunch of unused ctx files
5. Flip some ctx bits for speed.
6. Draw the rest of the owl, ie. implement a dedicated rasterizer task
   in components/st3m.

This implements the 'crtc' part of the graphics stack, ie. the task
responsible for blitting out a set of framebuffers over SPI as fast as
possible.

Currently this is still single-buffered, as the micropython API needs to
be changed to support injected, per-frame ctx instances.

This replaces the original GC9A01 driver with one optimized for our
usecase, implemented directly in a brand-new BSP (board support package)
component.

The major differences between the drivers are:

 1. aware of different badge generations
 2. generic: still supporting the possibility that we might have to
    switch to a different SPI display at some point
 3. only supports writing entire screen at once from in-memory buffer:
    no line drawing, filling, etc.
 4. spi screen blitting does not waste CPU time, instead uses
    ESP-IDF/FreeRTOS DMA/Interrupt logic to perform transfers
    efficiently.

We also drive-by enable SPIRAM, as we're starting to run out of memory.

p6, badge link: fixed pin indices. note: labels in schematic are wrong, should fix before publishing

Also drive-by removed unnecessary git submodule crud - we can now check
out all submodules without wasting time.

As part of the history rewrite we removed all unused micropython
submodules, so we don't have to use their machinery anymore to only
update submodules that are in use by our port.