start: name the requested --http-host/--http-port in the opening line

The first line was hardcoded to http://127.0.0.1:8080 while the flags
were passed through, so ./start.sh --http-host 10.0.28.161 printed
127.0.0.1 although the server bound 10.0.28.161 (its own listening banner
named it).  Both start scripts now parse --http-host/--http-port (space
and = forms, the last value wins like argparse) and echo the effective
address; start.bat parses with shift (%* is unaffected, so the server
still receives every argument).

Bump 3.38.2 (server, pyproject, PWA header, sw simple-v483) and add the
CHANGELOG entry.

Tests: tests/test_pcsc_startup.py pins the parsing/echo (2 new).
1090 Python + 1075 frontend.

frontend/sw.js

@@ -1,4 +1,4 @@
-const CACHE = 'simple-v482';
+const CACHE = 'simple-v483';
 const URLS = [
   'index.html',
   'help.html',