fix: removed uvloop entirely

[JinIgarashi]

fixes #519 RuntimeError: There is no current event loop in sync component code paths

Problem

rapida assess -c population crashes immediately:

File "/rapida/rapida/components/population/init.py", line 387, in download_compute
downloaded_files = asyncio.run(download_remote_files(...))
File ".../uvloop/init.py", line 206, in get_event_loop
raise RuntimeError(
RuntimeError: There is no current event loop in thread 'MainThread'.
sys:1: RuntimeWarning: coroutine 'download_remote_files' was never awaited

Cause

The asyncio bootstrap in rapida/cli/__init__.py:

• nest_asyncio.apply() replaces asyncio.run with a version that reuses the current loop via get_event_loop() — it never creates one itself.
• The uvloop policy installed right after it raises RuntimeError instead of implicitly creating a loop (uvloop 0.22 behaviour).
• assess is a synchronous Click command, so there is neither a running loop nor a registered one, and every asyncio.run(...) on a sync path fails.

Fix

remove uvloop entirely

- asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())