Pass platform_env_var="TELEGRAM_PROXY" to resolve_proxy_url() in both
telegram.py (main connect) and telegram_network.py (fallback transport),
so a Telegram-specific proxy takes priority over the generic HTTPS_PROXY.
Also bridge telegram.proxy_url from config.yaml to the TELEGRAM_PROXY
env var (env var takes precedence if both are set), add OPTIONAL_ENV_VARS
entry, docs, and tests.
Composite salvage of four community PRs:
- Core approach (both call sites): #9414 by @leeyang1990
- config.yaml bridging + docs: #6530 by @WhiteWorld
- Naming convention: #9074 by @brantzh6
- Earlier proxy work: #7786 by @ten-ltw
Closes#9414, closes#9074, closes#7786, closes#6530
Co-authored-by: WhiteWorld <WhiteWorld@users.noreply.github.com>
Co-authored-by: brantzh6 <brantzh6@users.noreply.github.com>
Co-authored-by: ten-ltw <ten-ltw@users.noreply.github.com>
c5acc6edb6