JLSEC-2026-624 HTTP/2 client HPACK desynchronization via header blocks for unknown streams in HTTP.jl

Description The HTTP/2 client's processincomingframe! dropped HEADERS/CONTINUATION frames for stream ids absent from conn.streams without passing the header block through the connection's HPACK decoder. Because HPACK's dynamic table is connection-scoped and mutated as a side effect of decoding ea...