WIP: Save agent roles integration work before CHORUS rebrand

- Agent roles and coordination features
- Chat API integration testing
- New configuration and workspace management

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

vendor/github.com/marten-seemann/tcp/ipv6zone.go

@@ -0,0 +1,73 @@
+// Copyright 2016 Mikio Hara. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tcp
+
+import (
+	"fmt"
+	"net"
+	"strconv"
+	"sync"
+	"time"
+)
+
+type ipv6ZoneCache struct {
+	sync.RWMutex
+	lastFetched time.Time
+	toIndex     map[string]int
+	toName      map[int]string
+}
+
+var zoneCache = ipv6ZoneCache{
+	toIndex: make(map[string]int),
+	toName:  make(map[int]string),
+}
+
+func (zc *ipv6ZoneCache) index(name string) int {
+	if name == "" {
+		return 0
+	}
+	zc.update()
+	zc.RLock()
+	defer zc.RUnlock()
+	index, ok := zc.toIndex[name]
+	if !ok {
+		index, _ = strconv.Atoi(name)
+	}
+	return index
+}
+
+func (zc *ipv6ZoneCache) name(index int) string {
+	if index == 0 {
+		return ""
+	}
+	zc.update()
+	zc.RLock()
+	defer zc.RUnlock()
+	name, ok := zc.toName[index]
+	if !ok {
+		name = fmt.Sprintf("%d", index)
+	}
+	return name
+}
+
+func (zc *ipv6ZoneCache) update() {
+	zc.Lock()
+	defer zc.Unlock()
+	now := time.Now()
+	if zc.lastFetched.After(now.Add(-60 * time.Second)) {
+		return
+	}
+	zc.lastFetched = now
+	ift, err := net.Interfaces()
+	if err != nil {
+		return
+	}
+	zc.toIndex = make(map[string]int, len(ift))
+	zc.toName = make(map[int]string, len(ift))
+	for _, ifi := range ift {
+		zc.toIndex[ifi.Name] = ifi.Index
+		zc.toName[ifi.Index] = ifi.Name
+	}
+}