This simplifies allocating outside of the VM because the VM doesn't
take up all remaining memory by default.
On ESP we delegate to the IDF for allocations. For all other ports,
we use TLSF to manage an outer "port" heap. The IDF uses TLSF
internally and we use their fork for the other ports.
This also removes the dynamic C stack sizing. It wasn't often used
and is not possible with a fixed outer heap.
Fixes#8512. Fixes#7334.
* Set nonblock on all accepted sockets. Not just ones for user code.
* Close an open websocket if another is accepted.
* Set debug level to INFO rather than DEBUG because DEBUG crashes
on ESP32-S3 USB OTG.
This uses the esp32-camera code instead of our own homebrewed camera code.
In theory it supports esp32, esp32-s2 and esp32-s3, as long as they have
PSRAM.
This is very basic and doesn't support changing any camera parameters,
including switching resolution or pixelformat.
This is tested on the Kaluga (ESP32-S2) and ESP32-S3-Eye boards.
First, reserve some PSRAM by putting this line in `CIRCUITPY/_env`:
```
CIRCUITPY_RESERVED_PSRAM=524288
```
and hard-reset the board for it to take effect.
Now, the following script will take a very low-resolution jpeg file and print
it in the REPL in escape coded form:
```python
import board
import esp32_camera
c = esp32_camera.Camera(
data_pins=board.CAMERA_DATA,
external_clock_pin=board.CAMERA_XCLK,
pixel_clock_pin=board.CAMERA_PCLK,
vsync_pin=board.CAMERA_VSYNC,
href_pin=board.CAMERA_HREF,
pixel_format=esp32_camera.PixelFormat.JPEG,
i2c=board.I2C(),
external_clock_frequency=20_000_000)
m = c.take()
if m is not None:
print(bytes(m))
```
Then on desktop open a python repl and run something like
```python
>>> with open("my.jpg", "wb") as f: f.write(<BIG PASTE FROM REPL>)
```
and open my.jpg in a viewer.
