Connect URL Parser failure

[Astaelan]

Based on hunting a customer issue for SignalWire, I came across the following issue that Claude was able to identify:

Symptom: Customer LaML <Connect><Stream url="wss://…/socket/twilio/agent:KlaraL"> fails on SignalWire with "Stream Error – The Connection was Refused"; same URL works on Twilio.

Root cause

URL-parser bug in libks kws_connect_ex at src/libs/libks/src/kws.c:1720-1740. The parser strips the port from the URL before separating the path, so the first : anywhere in the URL is treated as the port delimiter:

host = ks_pstrdup(pool, p);                 // p = everything after wss://
if ((p = strchr(host, ':'))) {              // finds ':' anywhere — including in the path
    *p++ = '\0';
    if (p) port = (ks_port_t)atoi(p);
}
p = strchr(p, '/');                         // search continues from past the ':'
if (p) { path = ks_pstrdup(pool, p); *p = '\0'; }
else   { path = "/"; }

Per RFC 3986, : is a valid character inside path segments (pchar). The customer's URL is well-formed; the parser is wrong.

Proposed fix (libks kws_connect_ex)

Split path first, then look for the port inside only the authority portion:

host = ks_pstrdup(pool, p);

/* split path first */
if ((p = strchr(host, '/'))) {
    path = ks_pstrdup(pool, p);
    *p = '\0';
} else {
    path = "/";
}

/* then look for port within host only */
if ((p = strchr(host, ':'))) {
    *p++ = '\0';
    if (*p) port = (ks_port_t)atoi(p);
}

Worth also handling [ipv6]:port while touching this block — the existing // if (*host == '[') // todo ipv6 comment shows it's been deferred before.