[Agent] Replace dockerapi container with Redis-based control bus

data/Dockerfiles/agent/internal/bus/lru.go

@@ -0,0 +1,38 @@
+package bus
+
+import (
+	"container/list"
+	"sync"
+)
+
+// lru is a tiny request-id deduplication cache. The bus treats Pub/Sub
+// retries (same request_id) as no-ops. Not a security boundary — only a
+// best-effort guard against accidental double-execution.
+type lru struct {
+	mu   sync.Mutex
+	cap  int
+	idx  map[string]*list.Element
+	list *list.List
+}
+
+func newLRU(cap int) *lru {
+	return &lru{cap: cap, idx: make(map[string]*list.Element, cap), list: list.New()}
+}
+
+// add returns true if id is new and was inserted; false if it was already
+// known (caller should skip the duplicate).
+func (l *lru) add(id string) bool {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if _, ok := l.idx[id]; ok {
+		return false
+	}
+	e := l.list.PushFront(id)
+	l.idx[id] = e
+	for l.list.Len() > l.cap {
+		old := l.list.Back()
+		l.list.Remove(old)
+		delete(l.idx, old.Value.(string))
+	}
+	return true
+}