* feat(settings): add proxy support for model downloads and update checks
Add a Proxy page to Settings (above About) with Off / System / Manual
modes. Manual mode supports SOCKS5 and HTTPS (HTTP CONNECT) proxies
with optional username/password auth; the password is stored in
config.json in plaintext like the other settings. System mode honors
the *_proxy environment variables and falls back to the GNOME
org.gnome.system.proxy manual configuration.
The resolved proxy is applied to every in-app outbound path that
fetches models or checks updates: the shared requests download path in
recognition_manager (_stream_model_download, used by the whisper.cpp,
whisper, Vosk, Parakeet and faster-whisper downloaders) and the
release checks in update_checker. A small Test Connection button on
the Proxy page verifies reachability through the configured proxy.
SOCKS5 needs PySocks, added as a runtime dependency; uv.lock, the
requirements/*.txt exports and the Flatpak dependency manifest are
regenerated by just lock (with a fix in sync_flatpak_deps.py for
packages like PySocks that publish more than one universal wheel).
Fixes#655
* fix(proxy): bracket IPv6 hosts, escape test errors, declare pysocks for AUR
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Co-authored-by: Jatin K Malik <jatinkrmalik@gmail.com>
