The Firecrawl provider used os.getenv() to read FIRECRAWL_API_KEY and
FIRECRAWL_API_URL, which only checks the process environment. When
values are supplied through Hermes's ~/.hermes/.env config mechanism
(via hermes_cli.config.get_env_value), they are not guaranteed to be
present in os.environ for every gateway/tool execution path.
Switch to get_env_value() which checks both os.environ and the .env
file, matching the pattern used by other providers (nous_subscription,
setup, discord adapter).
Fixes#40190