feat(routing): 引入多执行池智能调度

将 Worker 发现、路由画像、容量与执行传输抽象为平台无关接口，新增 Kubernetes 和静态容量适配器，并以 shadow 模式接入生产配置。

实现网络与容量评分、路由防抖、池队列、同步 Worker 租约、一次性执行令牌，以及提交状态不明时禁止重复分配的安全语义。

新增 0105 兼容迁移、管理接口、指标、OpenAPI 和回归测试。已执行全量 Go 测试、go vet、OpenAPI、迁移安全、Compose 与 Kustomize 验证。

apps/api/internal/executionpool/preference.go

@@ -0,0 +1,63 @@
+package executionpool
+
+import (
+	"strings"
+	"time"
+)
+
+type RoutePreference struct {
+	RouteProfileKey  string
+	CurrentPoolID    string
+	CurrentSince     time.Time
+	ChallengerPoolID string
+	ChallengerWins   int
+	UpdatedAt        time.Time
+}
+
+func AdvanceRoutePreference(
+	previous RoutePreference,
+	proposedPoolID string,
+	scores map[string]float64,
+	now time.Time,
+) RoutePreference {
+	if now.IsZero() {
+		now = time.Now()
+	}
+	proposedPoolID = strings.TrimSpace(proposedPoolID)
+	next := previous
+	next.UpdatedAt = now
+	if proposedPoolID == "" {
+		return next
+	}
+	if _, eligible := scores[next.CurrentPoolID]; next.CurrentPoolID == "" || !eligible {
+		next.CurrentPoolID = proposedPoolID
+		next.CurrentSince = now
+		next.ChallengerPoolID = ""
+		next.ChallengerWins = 0
+		return next
+	}
+	if proposedPoolID == next.CurrentPoolID {
+		next.ChallengerPoolID = ""
+		next.ChallengerWins = 0
+		return next
+	}
+	if relativeImprovement(scores[proposedPoolID], scores[next.CurrentPoolID]) < defaultSwitchImprovement {
+		next.ChallengerPoolID = ""
+		next.ChallengerWins = 0
+		return next
+	}
+	if next.ChallengerPoolID == proposedPoolID {
+		next.ChallengerWins++
+	} else {
+		next.ChallengerPoolID = proposedPoolID
+		next.ChallengerWins = 1
+	}
+	if next.ChallengerWins >= defaultBetterWindowCount &&
+		!next.CurrentSince.IsZero() && now.Sub(next.CurrentSince) >= defaultMinimumDwell {
+		next.CurrentPoolID = proposedPoolID
+		next.CurrentSince = now
+		next.ChallengerPoolID = ""
+		next.ChallengerWins = 0
+	}
+	return next
+}