chore: gofmt fixes across deploy-hardening I new files

Phase 13 verification surfaced gofmt-formatting drift in 6 files
across the bundle's new code:

- internal/api/handler/metrics.go (struct field alignment)
- internal/connector/target/k8ssecret/validate_only_test.go (alignment)
- internal/connector/target/nginx/nginx.go (alignment)
- internal/connector/target/postfix/postfix.go (alignment)
- internal/connector/target/ssh/validate_only_test.go (alignment)
- internal/service/deploy_counters.go (alignment)

Pure mechanical gofmt -w fixes; no behavior changes. CI's
make verify gate (which runs `go fmt ./...`) didn't catch these
because go fmt is more lenient than gofmt -l, but golangci-lint
v2.11.4 + the explicit gofmt step in Phase 13 verification did.

Phase 13 full-matrix verification all green:
- gofmt -l: empty across all bundle-touched files
- go vet ./internal/deploy/... ./internal/connector/target/... ./internal/service/ ./internal/api/handler/ ./cmd/agent/: clean
- golangci-lint v2.11.4 (the version CI runs): 0 issues
- go test -race -count=1 across deploy + nginx + apache + haproxy + agent + service: all green
- INTEGRATION=1 go test -tags integration -run Deploy ./deploy/test/...: 4/4 e2e tests green

Phase 14 next: release prep — Active Focus update, release notes,
Reddit-beat draft, final tag handoff to operator.

internal/api/handler/metrics.go

@@ -33,15 +33,15 @@ type CounterSnapshotter interface {
 //
 // Phase 10 of the deploy-hardening I master bundle.
 type DeploySnapshotEntry struct {
-	TargetType        string
-	AttemptsSuccess   uint64
-	AttemptsFailure   uint64
-	ValidateFailures  uint64
-	ReloadFailures    uint64
-	PostVerifyFails   uint64
-	RollbackRestored  uint64
-	RollbackAlsoFail  uint64
-	IdempotentSkips   uint64
+	TargetType       string
+	AttemptsSuccess  uint64
+	AttemptsFailure  uint64
+	ValidateFailures uint64
+	ReloadFailures   uint64
+	PostVerifyFails  uint64
+	RollbackRestored uint64
+	RollbackAlsoFail uint64
+	IdempotentSkips  uint64
 }
 
 // DeployCounterSnapshotter is the surface MetricsHandler consumes