TestTypedAccessors builds its ConfigManager with __new__ and, unlike
TestConfigManager, never patches CONFIG_DIR/CONFIG_FILE. That is fine
for the accessor tests, but test_whispercpp_advanced_persistence calls
save_config(), which writes the synthetic fixture from setUp over the
developer's real ~/.config/vocalinux/config.json — running the suite
silently wiped every personal setting. Caught by making the real file
read-only and running the suite with live logging; it is the only
write to the real path in the entire suite.
Redirect the paths to a temp directory for this test, the same way
TestConfigManager's setUp already does.
Co-authored-by: Jatin K Malik <jatinkrmalik@gmail.com>