Windows ships curl built against Schannel, which performs mandatory
certificate-revocation checks. When the user's network can't reach
OCSP/CRL responders (corporate firewalls, captive portals, IPv6
hiccups, some ISPs), the TLS handshake fails with
\`CRYPT_E_NO_REVOCATION_CHECK (0x80092012)\` and \`deepseek update\`
is unable to fetch \`api.github.com\` or download release assets.
Add \`--ssl-no-revoke\` to every curl invocation issued by the
self-update path on Windows. Other platforms (OpenSSL/LibreSSL on
macOS/Linux/BSD) continue to use no extra flags. Helper is a pure
function over the OS string, so both branches are unit-tested.
Hunter Bown
8f0bef9f15