Remove the now-unused forward declaration and the null checks that can no
longer fire, since create_session() always sets the session and its
context before installing the callback, and shorten the comments.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WGAYpQgXt95LdDQcJYgjB8
Every session now gets mbedtls_verify_callback(), which reads the user's
callback from the owning context when the handshake runs. The
has_verify_callback flag and the separate hostname-masking callback are no
longer needed, and a callback set after a session was created is still
honoured.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WGAYpQgXt95LdDQcJYgjB8
tls::set_verify_callback() kept the callback in a thread_local slot, so two
SSLClients configured on one thread overwrote each other's verifier, and a
client used from another thread ran none. Keep it with the context instead
(OpenSSL SSL_CTX ex_data, MbedTlsContext/WolfSSLContext member) and have each
backend trampoline look it up from the session's context.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013wxevjmRqzpy8qDAD3vdwr
Claude