The perplexity API key check in strix/tools/__init__.py used
Config.get() which only checks os.environ. At import time, the
config file (~/.strix/cli-config.json) hasn't been applied to
env vars yet, so the check always returned False.
Replace with _has_perplexity_api() that checks os.environ first
(fast path for SaaS/env var), then falls back to Config.load()
which reads the config file directly.
7dde988efc