- _build_ssl_context() loads certifi bundle + all *.pem from certs/ dir
- _SSL_CTX singleton built at module load, passed to httpx.get(verify=...)
- Fixes SSLCertVerificationError on Cloudflare-served sites on Fedora 43
(Comodo AAA root cert missing from system trust store)
- test_server.py: fix HTTPStatusError mock to include request= param