warn when the settled tree has outgrown its floors instead of quietly passing

internal/settled-tree-gate.mjs

@@ -111,7 +111,24 @@ console.log(
   ' quietFor=' + (quietFor === Infinity ? 'n/a' : quietFor + 's')
 )
 
+// ★ DRIFT WARNING — a floor that is never revisited decays silently while the tree grows.
+// This gate deliberately keeps LOOSE floors rather than deriving strict ones from manifest.json
+// the way check:drop does, because it runs DURING builds where a transiently empty tree is the
+// expected input; a strict floor here would fail on every clean phase. Different regime, different
+// tolerance — do NOT "fix" this to match check:drop.
+// But loose must not mean STALE. If the settled tree has outgrown a floor by a wide margin, the
+// floor has stopped constraining anything, so say so out loud instead of quietly passing.
+// (MIN_LEAVES=50 / MIN_DIRS=17 were set when the tree had ~58 leaves / 19 dirs — commit edb935f.)
+const DRIFT = Number(process.env.DRIFT_WARN || 1.35)
 if (ok) {
+  if (leaves >= MIN_LEAVES * DRIFT || dirs >= MIN_DIRS * DRIFT) {
+    console.log(
+      'SETTLED-TREE: NOTE — the tree has outgrown its floors (leaves ' + leaves + ' vs floor ' +
+      MIN_LEAVES + ', dirs ' + dirs + ' vs floor ' + MIN_DIRS + '). They still catch a CATASTROPHICALLY ' +
+      'gutted tree but no longer a partial one. Raise MIN_LEAVES/MIN_DIRS toward the current shape — ' +
+      'keeping headroom for mid-build transients, which is why they are not derived.'
+    )
+  }
   console.log('SETTLED-TREE: PASS — safe to measure or publish.')
   process.exit(0)
 }