feat: support name=host:port format in controller --peers

- 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

src/include/xce/cluster.h

@@ -10,9 +10,13 @@
 #include "config.h" /* MAX_HA_CANDIDATES, XCE_MAXHOSTNAME_LEN */
 
 /**
- * A single controller candidate (host + port).
+ * A single controller candidate.
+ * name: logical name from "name=host:port" syntax (empty if omitted).
+ * Matching against myconf->name allows multiple controllers on the same
+ * dev host to distinguish themselves by name rather than IP address.
  */
 typedef struct {
+    char name[XCE_MAXNAME_LEN];
     char hostname[XCE_MAXHOSTNAME_LEN];
     int  port;
 } xce_candidate_t;