* docs: add missing Telegram env vars to .env.example
TELEGRAM_API_BASE_URL, TELEGRAM_MESSAGE_THREAD_ID, and
TELEGRAM_USE_SYSTEM_PROXY were supported in config.ts but absent from
the example file.
* fix(config): read TELEGRAM_API_BASE_URL from environment
telegramApiBaseUrl was hardcoded to 'https://api.telegram.org' with no
env var override, preventing users in restricted networks (mainland
China, self-hosted bot-api servers) from pointing metapi at a proxy.
Now reads TELEGRAM_API_BASE_URL with fallback to the official endpoint,
trims whitespace, and strips trailing slashes — matching the pattern
already applied in notifyService.ts line ~80.
* fix: make telegramApiBaseUrl configurable via TELEGRAM_API_BASE_URL env var
Hardcoding https://api.telegram.org prevents users behind the Great Firewall
or running a self-hosted Bot API server from configuring a proxy base URL.
Read the base URL from TELEGRAM_API_BASE_URL (fallback to official endpoint)
and strip trailing slashes.
* test: cover TELEGRAM_API_BASE_URL resolution in buildConfig
* style: drop stray trailing newline
* fix(config): normalize TELEGRAM_API_BASE_URL before applying the default
* test: cover whitespace-only TELEGRAM_API_BASE_URL fallback
Fierushio