Optimize OTA

[Nerivec]

• Convert logic to async/await
• Add mock to test actual update logic
  • for now local only, takes too long for CI, even with fake timers that bypass throttling
• Move existing tests to TS
• Fix code styling, add typing, remove magic numbers for ZCL spec.

TODO:

• Better mock/test to allow CI testing of update (see above)?
• Test with actual device
• Test with devices known to have OTA quirks (Legrand, Sonoff, Bosch...)

[Nerivec]

Tests by @mundschenk-at (on network of ~80 devices)

• https://www.zigbee2mqtt.io/devices/929001953101.html
  • via coordinator
  • ~25min
• https://www.zigbee2mqtt.io/devices/929001953101.html
  • via router
  • ~30min

Notes:

• ETA appears to become pretty good around the 10% mark. A bit over-estimated before then.