Three identical static copies (controller, worker, scheduler) replaced
with a single xce_parse_peers() in src/lib/cluster.c.
The libxce version is the canonical implementation: stores the logical
name from 'name=host:port' syntax so daemons on the same dev host can
identify themselves by name rather than IP address.
- xce_candidate_t gains name[] field for logical peer identity
- parse_peers stores name prefix before '=' (empty when omitted)
- cluster_init matches own identity by name first, hostname as fallback
enabling multiple controllers on the same dev host via
--peers ctrl-1=10.0.1.1:7000,ctrl-2=10.0.1.2:7001
- myconf_t gains peers_cfg (xce_cluster_config_t) populated from --peers
- controller/main.c: parse --peers host:port,... via argp; ca_cert_path
auto-derived from workdir/certs/xce.crt (no --ca-cert flag needed)
- cluster_init: derive my_priority from position in peers list (index 0 =
primary); fall back to 0 when --peers not given (single-node mode)
