T13: klamp last_vote heuristik ke waktu scan (⊥ di masa depan)

Unstake tanpa revote membuat rasio bobot/stake membesar → estimasi
last_vote melewati now. normalize() kini mengklamp ke now; voters.db
dikembalikan (27 baris, MAX(last_vote) ≤ MAX(scanned_at)). Oracle lolos.

test_get_voters.py

@@ -147,6 +147,17 @@ def main():
                         'staked': 20000000,
                         'last_vote_weight': _fresh_weight(20000000)})['owner'] == 'new6')
 
+    # V13: estimasi yang melewati now (unstake tanpa revote) diklamp ke now
+    fixed_now = datetime(2026, 8, 5, 12, 0, 0)
+    t_future = ((fixed_now - gv.WEIGHT_EPOCH).days + 5) / 365.25
+    fut = gv.normalize({'owner': 'fut9', 'producers': [gv.TARGET_BP],
+                        'staked': 20000000,
+                        'last_vote_weight': f'{20000000 * 2 ** t_future:.17f}'},
+                       now=fixed_now)
+    check('V13 last_vote masa depan diklamp ke now',
+          fut is not None
+          and fut['last_vote'] == fixed_now.isoformat(timespec='seconds'))
+
     # V9: staked < 1000 VEX → dibuang; tepat 1000 → disimpan
     check('V9 di bawah 1000 dibuang',
           gv.normalize({'owner': 'low9', 'producers': [gv.TARGET_BP],