chore(fmt): repo-wide gofmt -w sweep — close drift surfaced by ci-pipeline-cleanup Phase 4

Mechanical reformat. The new 'gofmt drift' CI step (added in
ci-pipeline-cleanup Phase 4, commit 71b2245) surfaced 111 files
with accumulated gofmt drift across cmd/, internal/, and deploy/test/.

Each file's diff is gofmt-standard: whitespace adjustments, intra-
group import sorting (alphabetical by import path within blank-line-
separated groups), and struct-tag column alignment. No semantic
changes — verified via 'git diff --ignore-all-space' which shows only
the line-position deltas from import reordering.

The gate stays in place after this commit. Going forward it catches
gofmt drift at PR time.

internal/repository/postgres/health_check_test.go

@@ -235,8 +235,8 @@ func TestHealthCheckRepository_ListDueForCheck(t *testing.T) {
 	ctx := context.Background()
 
 	now := time.Now().UTC().Truncate(time.Microsecond)
-	pastDue := now.Add(-10 * time.Minute)   // > 300s ago, enabled → due
-	recent := now.Add(-30 * time.Second)    // < 300s ago, enabled → not due
+	pastDue := now.Add(-10 * time.Minute) // > 300s ago, enabled → due
+	recent := now.Add(-30 * time.Second)  // < 300s ago, enabled → not due
 
 	// (a) enabled + null last_checked_at — NULLS FIRST puts this first
 	a := newHealthCheck("hc-due-a", "a.example.com:443", domain.HealthStatusUnknown, true)