nx_cookie.nx

cookie.nx -- parse HTTP Cookie header (RFC 6265 §4.2). Parses the Cookie request header value: "name1=value1; name2=value2; name3=value3" This is the client-sent form that every HTTP server sees on every authenticated request. Used for: session IDs, CSRF tokens, language prefs, A/B flags. Nishi-pages + sovereign HTTP handlers need this to validate session cookies. Differences from query.nx: - Separator is "; " (semicolon + space) per RFC, though we also accept bare ";" for robustness. - No percent-encoding on names; values may be quoted with surrounding double-quotes (we strip them on parse). - Empty values legal ("foo=; bar=baz") means cookie deletion. Not handled here: Set-Cookie (the server-sent response header) which has many more attributes (Path, Domain, Secure, HttpOnly, SameSite, Max-Age, Expires). That's a separate set_cookie.nx shipper for the writer side. Invariants: C1 Zero-alloc -- offsets into caller's buffer. C2 Leading/trailing whitespace on names + values trimmed. C3 Quoted values ("foo") have quotes stripped; embedded escaped characters NOT unescaped today (RFC doesn't specify quoted-string escape semantics for Cookie).