A route may have its own listener: every request there is that route, paths unprefixed

Implemented-By: OpenCode session (model recorded in docs/implementer-log.md)

internal/config/route.go

@@ -2,8 +2,10 @@ package config
 
 import (
 	"fmt"
+	"net"
 	"regexp"
 	"sort"
+	"strconv"
 	"strings"
 )
 
@@ -22,6 +24,7 @@ type Route struct {
 	Peers        []string `toml:"peers"`
 	Affinity     string   `toml:"affinity"` // "" or "conversation" (the default), or "route"
 	Queue        *bool    `toml:"queue"`    // nil means true
+	Listen       string   `toml:"listen"`   // "" = none; else host:port of the route's own listener
 }
 
 // PerRoute reports affinity = "route": every request on the route (chat or control) shares one
@@ -80,6 +83,9 @@ func (c *Config) checkRoutes(peersDefined map[string]bool, identityDefined bool)
 		names = append(names, name)
 	}
 	sort.Strings(names)
+	// A route's own listener address, keyed for the uniqueness check: the value is the
+	// route that first claimed it, so the second route in sorted order reports the miss.
+	seenListen := make(map[string]string, len(c.Routes))
 	for _, name := range names {
 		r := c.Routes[name]
 
@@ -124,6 +130,39 @@ func (c *Config) checkRoutes(peersDefined map[string]bool, identityDefined bool)
 		if e := checkPeers(name, r.Peers, peersDefined[name], identityDefined, c.Identity); e != nil {
 			return e
 		}
+
+		if e := checkListen(name, r.Listen, c.Listen, seenListen); e != nil {
+			return e
+		}
 	}
 	return nil
 }
+
+// checkListen validates one route's own listener. The rules, in order, each naming the key
+// routes.<name>.listen: the value must split into host and a numeric port 1-65535, it must not be on
+// a template route, it must not be the top-level listen, and it must be unique across routes (the
+// second route in sorted name order reports the clash and the other route's name).
+func checkListen(name, listen, mainListen string, seenListen map[string]string) *Error {
+	if listen == "" {
+		return nil
+	}
+	_, port, err := net.SplitHostPort(listen)
+	if err != nil {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: "must be host:port"}
+	}
+	n, err := strconv.Atoi(port)
+	if err != nil || n < 1 || n > 65535 {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: "port must be 1-65535"}
+	}
+	if templateName.MatchString(name) {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: "a template route cannot have its own listener"}
+	}
+	if listen == mainListen {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: "cannot be the main listen address"}
+	}
+	if other, dup := seenListen[listen]; dup {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: fmt.Sprintf("already used by route %s", other)}
+	}
+	seenListen[listen] = name
+	return nil
+}